Just got braces, and my advice would be:
* Liberally apply lip balm right before being braced... it's worth it!
* Be prepare to not be able to chew on anything for at least a week. Okay, I have no idea how long this no-chewing thing lasts, but it's been 3.5 days and I still can't chew on anything that isn't super mushy. Some people don't experience this, so cross your fingers.
* Carry a toothbrush with you everywhere. Actually, even more important than a toothbrush is a proxy brush (x-mas tree shaped brush) which gets between your brackets. It's really disgusting, yet strangely fascinating, how much food can get stuck between your teeth!
* Since you will have clear brackets (which I'm a bit envious of at the moment), be careful to avoid anything that could stain the clear ligs that will be placed on them. Your ortho will change the ligs at your adjustments, but no-one wants bright yellow circles on their teeth for several weeks! Curries are apparantly the worst culprit, but pretty much anything that can stain clothes can stain your ligs. So brush often and think before you eat!
* There is nothing wrong with taking pain killers. It's okay to be a wimp, like me
* On a similar note, don't forget to take dental wax around with you! I forgot it one day at work, and by the end of the day I had some nasty mouth sores. Everyone is different though, so hopefully you won't experience this. But better safe than sorry!
Oh, and I have a mouth full of metal and I haven't tasted it. I did taste the glue used to put my brackets on for almost an hour after I was braced, but that disappeared quickly enough.
Good luck!