Alright it seems like you are not leading and not being the sexual aggressor. This is important.
You have to make the first move in this. You can do this, it just take balls. One in 50 or one in a hundred girls might walk up to you with interest and start a conversation. Don't rely on this whatsoever. You walk up to her, or if you are introduced, shake her hand, hold it, hold eye contact and speak with confidence. This is easier said than done, especially when starting out.
I suggest you read some stuff. There are some great books out there, the ones I would recommend are:
The Attraction Code by Vin Dicarlo
60 Years of Challenge (all 4 books preferably, but books 1 and 2 are the core)
Vin Dicarlo's Escalation Ladder
What do you talk about? Absolutely fucking anything. Last night I walked up to a girl in a bar who was clearly waiting for someone, and she said it was her boyfriend. I didn't hear, so I said "You're waiting for your imaginary friend? Is this Bob? Hi Bob. I also have one imaginary friend. Actually half of one. He's only got legs. It's great cause you don't have to feed him."
Self amusement. I really didn't care what she thought. There are a few mindsets you must adopt to get good at this. It's not all what you say (of course being witty is great and all, but the deeper mindset helps you get there without thinking about it at all).
Have fun. Go out and have fun, enjoy yourself. Have a laugh with your friends or with your fellow PUA. Fuck it get rejected. Who cares? Mess with people a bit. Mess with girls a bit. Tease them, push them, pull them, go on roleplays with them (Let's fly to Pluto and create a new civilization. You build the spaceship, I'll bring the camera). Disqualify them for the heck of it (This will never work out between us). Flip the script (Look, I know you're flirting with me, but I'm not that easy, I have to be wined and dined first). Be cocky and funny (Look, if you really wanna see this sexy face again, you'll have to wait til the next full moon, I only go out when it's werewolf season). Whatever. This all falls under the category of HAVING FUN.
Know what you want and go for it. I want to talk to her. I want to get her number. I want to get her out on a date. I want to HAVE FUN WITH HER. Whatever your intention is, KNOW IT and GO FOR IT. Without any apologies whatsoever. So if you want to hit on her, make it clear you are doing so. This shows extreme confidence. Why? Because an Alpha male, with all his options, will just go up to a girl and make his intention clear, because he knows he is the prize. He is bringing her into his life. So bring her into your life. Into your world. He knows he has higher value than them. He ASSUMES ATTRACTION from the start. So do so. Just assume attraction. "I know this girl wants me. I just have to help her cross her social barriers and her anxiety (her ASD and her Bitch Shield). She's just nervous. She's got a bit of an ego. With that knowledge go in there and talk to her. You know she wants you, and you know what you want, so go for it. Make the move. SAY AND DO WHAT YOU WANT. And of course HAVE FUN.
Say and do what you want. Literally say anything, do anything, as long as it is for yourself. Fuck her and her thoughts and feelings. You're having fun. So if you feel like having a conversation about rainbows, do so. If you feel like dancing, do so. If you feel like playing a game, do so. LEAD the interaction by saying and doing whatever you want and going for it. FUCK EVERYTHING AND JUST SAY AND DO WHATEVER YOU WANT.
Be unapologetic. As said above, do not ever apologize for anything you say and/or do. An Alpha male never apologizes, because he knows what he says is just him expressing himself, and the other can either take it or leave it. He doesn't cater to other people's feelings, because why should he? He doesn't even know her yet, and hasn't earned his caring about her feelings yet. She could be a total bitch for all he knows. (But he knows she's attracted

) So don't apologize. Even if you mess up, DON'T APOLOGIZE. You are learning. Know that. Just note it and work on it. But in the moment do not apologize for anything. This means you can talk about penises on unicorns and have the time of your life laughing your ass off, and she looks at you and says "That's rude and disgusting." What would you say? "Sorry I didn't mean to be rude. I hope I didn't offend you." Or would you say "Oh crap, someone call the humor police, someone doesn't have a sense of humor!" and continue laughing? This is your world, she either joins it or doesn't. But don't join hers. You have the frame control here, and you bring her into her frame. She jumps into your loops before you agree to jump into hers (the basics of hoop theory). You stand your ground. You are the man, the one that makes the move, so be that man. She will actually appreciate it more if you stand your ground rather than suck up to her, even if she thinks you are rude or disgusting. She doesn't see you as a friend, but you ARE a sexual candidate. Why? Because you are a man without apologies who goes for what he wants and has fun doing so all the time. You are an alpha male you doesn't care about her feelings (initially at least). She can come have a great time with you, and you'd be more than happy to have one with her, but you don't HAVE to have a great time with her if she doesn't join you. You can just MOVE ON to the next one who does have a great time and sense of humor. This is called SCREENING.
Be unaffected. Basically what I've already said in the last point. Be unaffected by her shit. Don't take her shit. Be non-reactive. This is your world. Shit tests are congruence tests. They are there to find out if you are who you really say you are. Are you the person you make yourself out to be, or not? This means that should you say something like "I think you're cute." And she goes "Do you say that to every girl?" Now, there is no right answer to this, only a right MINDSET to passing this shit test. You can pass it with "Yes. You are the 332 girl I've said it to tonight." The playful way. Or, "No, I genuinely thought you look cute, but is there more to you than just your looks?" The genuine and confident way (if you really do mean it, it will come out right). You fail it with "Yes, but actually you're not that cute." < Incongruence plus being an asshole. This is not a shit test I would "ignore" as there are some you can just bypass by not answering at all.
Stay unaffected by anything she says and/or does. If she turns around from you, talk to someone else and stay upbeat. If she shit tests you, stand your ground and wave it off playfully or genuinely. You can pass many shit tests by saying "Cool story bro" or "Good for you" like if she says something stupid like "You dress weirdly." "Cool story bro." Who cares what she thinks? She doesn't control you. You control you. And if you like what you wear, then stick with that. Don't change yourself for her. Ever. Only if you ever get into an LTR for a while may you compromise here or there. But don't change your personality for her, ever. You like what you like. You are who you are. And that's it. You are bettering yourself to becoming the best that you can be.
Qualify her. You have standards. An Alpha male has standards. He doesn't just fuck anyone or anything that walks. He knows what he wants, and thus goes for that. So write down a bunch of things you want in a girl. Can she cook? Does she like to travel? Is she adventurous? If she says she is ask her what the most adventurous thing is she's ever done. Does she like good food? Is she classy? (This you can usually tell by her attitude or what she says and/or does - if she does something you don't like you can DISQUALIFY her, like "You watch Twilight?" And just give her a disgusted look. So know what you want in a girl and SCREEN her for it. If she really doesn't fit your standards, move on to the next one. Another standards can be that she is an open person, so if she is all bitchy from the start, obviously you can try to break through that or help her lower her shield, but you can also just say "Nice meeting you. Bye." and move on to the next one who might actually be open to your approach.
Be dominant and lead. You have to always make the first move. YOU decide where the conversation goes and where you both go, even for a second date. "Let's go to ... on Sunday. They make great ice-cream there." Whatever. Don't ask. Make statements. Cold-read her on what she's wearing "You look creative." "You look like a bit of a bookworm. But a hot bookworm so I guess I can let you off this time." It doesn't matter if you're right or wrong. What matters is the deeper sense, the bigger picture. You're not showing THAT much interest in her. If you ask her, that is a clear IOI from your part. But if you make a statement, you're just having fun. You're making a statement based upon your observations. Sometimes you will have such a great time that you will just lead naturally. You vomit your fun and personality onto her. You talk much. You don't always have to talk much. Being dominant entails ESCALATING. You have to escalate escalate escalate.
Shut the fuck up. Take right out of 60 Years of Challenge. The one talking is the one qualifying. Qualify her (ask her a question from your standards list) and just SHUT UP. If she stop talking, see if you can hold it. Build the tension. This is sexual tension. She will want to break it. But just hold it. Hold it. This is a crucial moment. She will get nervous and maybe look away. She will then restart the conversation with anything. You have won. She broke first, you can handle more sexual tension than she can. Don't give her big smiles or nods when she talks, and don't say "Yeah, uh huh, Oh I know right?" Shut the fuck up. A blank expression. As 60 says "50% of you is screening her, 50% of you is checking her out." Read 60 Years of Challenge for a much more detailed explanation of his method.
Build a connection. This means geting to know her, that's all. Find commonalities and work on them. Tell her what you like, and find out what she likes. Let her talk more about herself than you do about yourself (of course you can also just vomit your personality onto her, but after a while, when she's interested, this is just arrogant and you should take the back-seat and just let her talk while you eye-fuck her). People love talking about themselves. Don't apologize for trying to find out who she is. You're trying to fucking get to know her. Be forward with your questions and with your topics. Escalate the vibe. Escalate the talking and the touching. If she can't handle it, then move on (this can also be one of your standards - is she comfortable with taboo topics, or sexual topics, or just me advancing in general - does she have sexual hangups?)
Escalate. This means touching. You are a touchy feely type of person. That's just who you are. And you never apologize for it. If she doesn't like it then that's her problem. This is just who you are. You are sexual. You like girls, you like sex, you like to touch people. Whatever. So what? Hone your touchy feeliness. Touch everyone and everything. Make the move on the girl, touch her, without apologizing for any of it. You're hitting on her goddamnit. So touch her. If she resists, doesn't matter, don't mention it. Take a step back and go for it again. Be sexual. Be dominant in your touch, lead the touching, lead the vibe. Raise it up a notch every time. Get to "no". Get close to her. Look at her. Eye-fuck her. Touch her shoulders, arms, back, hands, lower back, legs, face, hug her tightly. Let her go. Push and pull her in and out. Create sexual tension with silences and a dominant calmness by just looking at her. Make her pupils dilate. Handle the sexual tension, don't break it. Don't break your rapport with her after you have had fun together. Don't fall for her traps of breaking rapport either after a certain point. There comes a point where you just want to move things forward and escalate. Fun and games aside, be genuine and confident in getting close to her now. Escalate. Make it official there is a spark between you two, a sexual connection. Touch her more and more. You have to take responsibility for moving things forward. She has to be able to blame you. You are to blame for what is happening between the two of you. That's good, you lead. That's attractive. She has to feel like "it just happened" or "he was just not letting it go." Be persistent, keep at it again and again and again, because you WANT TO. It's the only way to get there. To get her. Escalate.
Alright, there is a lot more to this thing in general, but many things overlap. These should be the key points to your inner game, to your MINDSET.