I'll second what TinkerBrie says about the lotion! Make sure your nails are nice and clean because any oily film on the nail, even what's naturally there, will impede the nail polish. And while this is not really applicable for the pedis but will work for the manis, don't touch your nails to see if they're dry!!!!!!! If you NEED to touch them, touch them to your lip rather than with your fingertip so you don't leave a fingerprint. I also heard that if you put water on your nail and it beads up, the polish is pretty well dry. The last thing I can think of (most of this is personal experience, figured it out long before cosmetology class lol) that if your nail polish is thick (like several coats), and dry, and you put another coat on, it will "rehydrate" the other coats and if you knock your finger against the edge of anything you'll end up with a dent in the polish.
Oops one more thing since I just saw a commercial for Alice in Wonderland. The glittery top coats are just that, top coats. I had OPI Chip Skip on, then a base coat, then 2 coats of OPI Absolutely Alice (which looked great), once I had my hands in water, it came off a kids press on nail.