Most Helpful Guy
Well asking out is one approach but I get it if you don't want to do that.
If you see a guy you think is cute and you'd like to talk to then you need to give him clues of your interest (most guys will not bother trying to flirt with a girl unless they think their odds of success are good. Guys hate rejection just as much as girls). So that means trying to make eye contact and when you do make eye contact hold the eye contact and either smile, play with your hair, wave to them, or bite on your finger or any combo of those.2
Most Helpful Girl
Ask a guy out and see what happens...2