Anonymous
Some of the most common I noticed:
They'll start a random convo with you out of nowhere (or usually a bunch of times)
They'll keep looking at you.
They'll smile every time you walk in their direction.
MCM
Stares at u ,looks uinda eyes does a lot for u , goes out of his way for u
choko_canyon
He asks you out.
janey
kjhsajhfjashfsaj
KTJoe
Talks excessively always in your space, most of all he says you're hot.