It all depends on what you are trying to mimic. If you are using a color to try and mimic a crayfish than dragging it accrossed the bottom or small hops are the way to go, but in all honesty a tube or small skirted jig with trailer would probably work better in most cases for this. Grubs still can work great though....
Most of my grub fishing is with baitfish colored patterns and is fished to mimic baitfish. I try to rig them with lighter jig heads so they have a stalled effect on the drop, just try various twitches, jerks, and retrieves to see what works best at that time....