There will be a lot of answers telling you to read X books ect. I will give you my peace of advice because I was(still...but not really, I will explain) like you.
I don't call myself a PUA, I am able to open but I find hard to create sexual tension. Anyway what I did it's to work on my Inner game. Even if you read the best openers, you will need the guts of doing it. If you finally find the courage of going opening a set, if you are nervous it will fails for sure. So work on your inner game, in my opinion it's the most important thing. It's not only good for picking up women, but also in your life, your job ect. When you feel in security doing something, you will give the vibe that you are confident and strong. I can't continu this post for the moment because I am going out.
Good luck.