Basic Riding Skills — Effective Shifting

Shift smoothly AND with maximum style
Shifting a bicycle is easy, but shifting it well — so you aren’t throwing your chain, putting undue stress on your drive train and making HORRIBLE grinding noises as you change gears can be a bit more of a challenge. Here are a few articles I’ve found to make the learning process a bit easier:
This one is from an old-school mechanic and is rather amusing.
This one provides a little more deal (and talks about cross-chaining and trim).
This one is for the layman.
This one covers a lot of other basic skills as well.
Read them all.