Have you watched Schitt's Creek? If not, skip to the episode where Moira gave advice on picking up men to her daughter Alexis. The advice works on both men and women.
After you have made contact with someone, such as swapping numbers, make sure to touch their hand, ever so slightly touch the middle of their back, or lightly touch their hair, etc.
It's called the love language of "touch". It may not work on the first person you try it in, maybe not even the second, but by the time you have tried it on the third person, someone's heart has melted… even if the effects aren't immediate.
I have used this method all my life. It works 100% of the time unless the other person genuinely isn't interested in a relationship with you, or if they're already taken. People enjoy knowing someone is interested in them. If used with tact, no one would take offense to a slight touch on the hand when swapping numbers and doing so will only GREATLY improve your odds.
Any women in here want to tell me I'm wrong? Any men?