There is a method for slicing as well that, if practiced all the time, will impress your audience into thinking you were raised and trained in a Japanese steak house....well, slight exaggeration there, but it does work.

If you're right handed, hold your food with your left hand fingertips, palm down in a claw grip. This is your cutting guide. Knife in the right hand, it's all in the wrist. I can slice a bowl of fresh mushrooms [1 lb] at consistent two millimeter slices in less than two minutes. I'm at it so fast that mushrooms are flying in the air around me...okay..so I b.s. a little. You will develop speed when you consistently employ your method.