Whether you are just starting out as an artist or you feel like your progress has stalled, these tips and suggestions from various DA members may help you to continue moving forward. I've paraphrased and edited in some cases to showcase the tips that I found particularly insightful.
For inspiration, check out Mindcandyman on conceptart. Look at the first couple of pages of his sketchbook (2002) and then jump to about page 40 (2004) to see how far someone can progress in about 2 years (and beyond): http://www.conceptart.org/forums/showthread.php?t=870&page=41
Studying realism would be a good first step. Even if you want to work in, say,