| I havn't seen any vids specifically for 6 string slap, but my experience w/ learning to slap on a 6 is just practice. When I was trying to figure it out, I could slap w/ my thumb just fine but I couldn't pluck for crap. The string spacing was too close. I found that by keeping your plucking fingers really close to or on the higher strings made it easier to "find" the right string. I'm used to playing 5's so the transition wasn't that dramatic. I have no idea if these are any of the problems you're having, but I hope this helps. | 
Is there any slap video made for sixers? 
