hand care

what/what not to do before/after practicing?

Nothing special ... For the fretting hand , always have short nails , and avoid chewing the skin at your finger tips to always have them strong enough for bending and sliding stuff.
Same applies to picking hand if you're into finger tapping.

When the weather is a little cold , I blow hot air from my mouth into my both hands and rub them together before warming up with chromatics.

In John Petrucci's video , he explain some exercises for the hands , but I don't find them necessary at all.

I find those exercises VERY necessary. I do them everytime before i start praciticing! plus it is very important to have a good playing position and a very relaxed playing at all in order not to tense up everything, cuz that can lead to serious troubles starting from simple headaces to tendonitis and what not.

so thats why I wake up with pounding headaches after playing the next morning.... hmmmm go figure...
and no I don't drink...much....anyways it's not the beer...

Don't play immediately after taking after a shower, or swimming in the ocean. Your calloses *sp* won't be solid, and it has a tendency to tear of the calloses. In cold weather though I do soak my hands in warm water for 30 seconds to loosen my muscles.

I never do any exercises or anything but sometimes
I wash my hands in warm water to get rid of any
dirt, grease and such that can make your fingers "stick" to the fretboard.
+ you loosen up your muscles.

I dont do any exercises, but I always play in a comfortable position and stop playing if my hand hurts or whatever. And about the shower thing, Ive been playing for 3 years and showers still rip my fingertips apart, but thats cos I go for runs every morning then shower so never really have a chance to build them up. Izzy Stradlin from GnR used to go weeks without showering to keep his fingers hard, my girlfriends making sure I dont go down that road!