I was watching filmmaking lectures at work.... and I was reminded of a great concept, that I think is completely applicable to artists of all kinds:
Focus on something small.
Script Consultant, Pilar Alessandra, was talking about how to improve as a screenwriter, and how one great tool she teaches her students, is the concept of tackling only a small, focused goal, instead of trying to write The Godfather in one sitting.
Just write three pages. One scene. One cool line of dialogue. Focus on that one small part of the machine, instead of trying to tackle the story as a whole.
The connection to art that I made was something I have always struggled with: being utterly overwhelmed with EVERYTHING I have to do as an artist..... I need to practice anatomy, I have to see light perfectly, design, storytelling, improving, finding the perfect pencil.... blah, blah, blah!
My dad has always helped keep me conscious of this same idea of focusing on the next step in front of me. I always tend to want to leap and bound forward, stumbling horrifically every time. And he always reminds me to take just one step forward. Just take a baby step.
Paint for one hour, and whatever comes of it, move on. Don't try and paint the Mona Lisa in one sitting. Do a study of a bush. Draw your hand in a minute. It's probably, most definitely, absolutely not going to meet your standards on the first swing. But you got that crap out of your system, and you move on.
Whether you're writing a scene for a movie, or designing a character, focus on accomplishing small things, in anticipation for them to become the larger achievement. You'll be very surprised how much you're able to get done.