How do you know If He's into you?

Check for protrusions lol

Well firstly if he is into you, you normally don't need to ask
because he shows you. It's when you have to question if he is that he
normally isn't....in my humble opinion any way

You never know unless he tells you.

when he says it ten thousand times haha.
or compliments you and it is super obvious or acts weird.

Indicators of Interest. Observe the list:

http://www.simplepickup.com/forum/questions-advice/2876-iois-indicators-interest.html

has you pinned against the wall

If he misses you when you're not there,knowing if he's not just saying that is a different thing

well he could just be after sex. with people now a days its just a game.

like that Cher song , its in his Kiss