ShortHoppin does take some time with fox to perfect but you will notice a level of ease after a bit of praticing. A easier way to do it (for me) is to sorta flick the analog stick (if you wanna learn the analog sh..) or If you wanna learn X or Y eaiser (for me anyway..) try softly tapping the edge of the button. You will have to focus on it at 1st but youll eventualy get it down. Just pratice in training mode for a bit, then after a good long session try playing that computer of yurs and try implementing it ingame (even if yur just doing it between stocks), this will get you used to shing under pressure.
Errr basic things to be good with fox.. Dont hesitate to grab. Foxes Uthrow>Uair is a nice, simple, way to get the kill. Learn to use the shine, even if you dont use it often, read the shine guide in the boards and... dont forget to taunt after a kill =p.