You need two things: Attraction and rapport. Calling that cute girl from last night that you got really horny with the interaction not going anywhere is a flake. You're still a stranger, she didn't get to know you and you didn't bother to get to know her. That's what happens when you focus too much on making attraction official. But spend too much time talking and building rapport and you end with being in the friend zone.

Phone numbers. Always, always call/text immediately after she gives you her number. This verifies her number and gets your number saved. Most guys think it's desperate but only because they don't know how to be smooth. You simply text her, "I'm Chris, this is my number." That way when you call her the next day, you will already be in her phone book. The chances of her answering are much higher. She will look at her phone and see either +13882325928 or "Chris".

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Don't get on one knee for a girl that won't get on two for you.

Stellar advice great post for the FAQs

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They call me the cat whisperer, cause I know exactly what the pussy needs.