tips on how to air a quarter?
and how to ice pick on quarter?

Basically you should definitely learn how to double peg stall the quarter before you try a ice pick. With that aside, you should get a decent amount of speed, go up the transition and go off. Ha its really not that hard, if you feel like your going a bit sideways just place your foot out to catch yourself (if its that kind of quarter with a deck)

Watch the Tom Dugan Full of Hot Air video, best tutorial out there