Lots of practice. Lots of looking at others work and wireframes and such. Study anatomy, get some good reference photos.

I went to school, but realisticly, upon graduation, I had only been taught the basics. I was then hired at the same school as a teacher's assistant and learned a lot that way.

I work as an artist at a video game studio, after about 3 years AFTER graduating from school and continued practice to better myself.

Unfortunately, my current website doesn't have very good work that's indicative of my current quality, as most of the stuff I've done over the last 6-10 months I can't show.