How do you tell if a guy likes you?

well you see him watching you jokes and messes around gives you a hard time is hanging around you or tells your friends how he feels or have one of them set him up with you pulls stunts wants to hang out alot messages you if he has your cell number goes out of his way to talk to you hangs out and waits in the halls for you to come buy things like that and wants to know if you like him