I am teen and i have only kissed 1 boy before. You shouldn't be giving you should want to be more than a flipper (hit her then ditch her). You shouldn't even kiss at a young age. That lets many...
Well, if you want to do a long kiss, you tilt your head the opposite direction of the person your going to kiss and then slowly move your lips toward theirs until they touch.
If you are also a 13-year-old asking, then a kiss on the cheek or lips may be ok or appropriate if the other person is in agreement. If you are older than the 13-year-old then you shouldn't really be...