might i put in my 2 cents?
first off ive only been playing for a year and 8 months, ive had no mentors or teachers... everything ive learned was pretty much self taught.. tho went and watched people slap alot at shows. so a few months ago i figured id try it.. first off for those whom are wanting to do it i suggest you try just slapping and popping octaves. for instance...
g---5-------7-----------------
d------------------5--------7-
a-3-------5-------------------
e----------------3--------5---
just do that nice and slow and steady.. you'll find that if you just keep all four fingers somewhat close together.. you can easily mute the strings. now heres the fingering for the excercise... the E and A strings of course would be the thumb slapping on the right hand, and for your left hand you would use your index finger for the fret. then for the pops on the G and D strings i personally use (right hand BTW) my middle finger mainly for just about every pop. but im sure others can back me up about others use their index finger to do most pops. as for the left hand during the pop, this is also an optional thing.. most either use their pinky(I do) or their ring finger. which ever is more comfortable i suppose.
hope this helps
