Well if you don't have enough points to max both foh and holy shock like if you were makeing a v/t that was more on the smite side then this link should help:
http://www.purediablo.com/forums/showthread.php?t=172668
with foh I like to use conv so at least 1pt in this would be helpfull or what I did was for my v/t was make a cta in a +2foh +2conv scepter and didn't put any points into conv at all. That saved me 3 skill points that I got to put into foh/holy shock instead.