Which method helped you become a better coder?

There isn't a single method that has made me a better coder, but here are a few things I've picked up over the years:

1. Be around both experienced coders and those still learning how to code and TALK to them! Make sure that you're around supportive and productive people.

2. Find, read and hack around with code that is slightly above your skill level

3. Code, code, code - you won't make any progress just reading and talking about programming

I emphasize the first bullet - being around the right people and environment has given me the opportunity to grow so much faster as a programmer than I would have if I had done things alone by myself. Learning is a highly social human endeavor; why should learning how to code be any different? The image of the lone programmer that sits in his cube through all of his days without any social interaction is a myth and reflects poorly on the real software engineers of today. Don't be afraid to get out there!