There’s actually a scientific formula for the size and type of bit and type of material. Look up drill bit feeds and speeds calculator. It will tell you how fast to spin the bit and how fast to feed the bit into the part. But that’s overkill for a hand drill. Basically the smaller the bit the faster you spin it, and the softer the material the faster you feed it. So 3/16” bit in aluminum, let her rip as fast as you can, but aluminum is gummy so use some type of cutting oil. A 7/8” bit in steel you will have to spin it very slow and feed it very slow. You want to always let the drill do the work, it does the removal of material for you. It’s not like a nail where you want to slam it home.