Possibilities for using the Foot-Switch?

For me sometimes it would be best to have the beatbuddy in hands-reach while standing. For changing folders, choosing songs… Starting a song by hand-pushsing the main button is possible, but how shall I get fills, transitions (f.e. pressing 1 st. button short and long?). I saw some setups with a beatbuddy upwards. What functions do you set to the foot-switch?