I have
exactly the same problem, and it boils down to: I'm too hung up on results. If I draw a picture, I want it to be a damn
good picture - otherwise, what's the
point?
Steve's latest podcast (
http://www.stevepavlina.com/blog/200...l-achievement/) was a revelation to me regarding this question. In order to achieve a goal, you need to transition to
being the sort of person who has achieved that goal.
The point of drawing is to
be the sort of person who would draw an awesome picture. That person wouldn't be freaking out if a given picture failed. They'd be going "Bugger. Okay, how about if we try
this?".
IMO, "Try drawing for 15 minutes no matter what" is actually bad advice. I've tried that approach myself with no success. I think the main reason for hat is it makes drawing into a
chore. You don't want to force yourself into doing it - yourself will just rebel.
Instead, jump to the finish line.
Be the magnificent artist (pick a particular one (eg. Leonardo Da Vinci) if you like). Would the artist say to him(or her)self "I really must set aside some time later to do art"? Of course not! They'd say "Cool, A spare moment! Now I've got a chance to refine how I draw feet!".
We get so caught up in what we have to do to achieve our goals. But if we be the sort of person who'd achieve those goals, the doing just flows naturally.
P.S. Steve's podcast also talks about environmental reinforcement. For an artist, that means things like having a sketchpad nearby (or on you!) at all times, having numerous art reference books handy, surrounding yourself with your art, etc.