foot warmers have adhesive on one side so they stay in place. if you are filming and your cameras battery is exposed (most are) you can stick a foot warmer to the battery, keeping it warm will make it last longer.
dont wear thick ski socks, wear either regular or thin socks, your feet will stay warmer.
be nice to all the employees of whatever mountain you are riding at, a little bit of kindness can get you very far.
if you're having a bad day, or someone/something is bothering you, write your problem or the name of the person/thing bothering you on the base of your skis in sharpie. then get out there and ski until you cant read what you wrote anymore.
unless you are racing, just wax with cheap parafin. as long as you get moisture into the base of your ski, you will still get all of the positive effects of using expensive high-end wax. just a little less speed.