Bone shears, scissors, hammer/chisel and Dremel tool are the ones I work with for the different types of corals.
As far as technique goes, you'll find lots of info at
www.garf.org. You'll just have to bear with the mad family cheese that permeates the entire site.
Personally, I just look at a coral, evaluate whether or not I can even make frags then "go at it". Most corals can take pretty severe abuse.