#1
Attempting a somewhat fast song. I can get it down sometimes but sometimes I can't. Would it be better to practice exercises to target all my fingers in hopes of tackling this hard song or just keep practicing this one particular piece?
Thanks
#2
in the long run, just practicing should be exercise enough.

If Its a "somewhat fast song" and your having trouble playing it up to speed, try working it slower.

Just turn the tempo down a little bit and play it as steady as you can, and get comfortable. Practice at a comfortable speed and turn up the pace little by little every day.

This is how you master a "peice"