I have been following a process that I watched on a DVD by Feng Zhu that Alan suggested I watch. It entails drawing entirely silhouettes as opposed to becoming bogged down with details.
I picked up a few interesting points. Firstly, he thinks of the drawing of three 'parts.'
1- A big strong shape. This could be the head, torso, anything, but a feature that should be big and strong.
2- Secondary shapes. The ones that aren't the big strong one. These could be legs, torso (if the heads the strong feature) and arms.
You could mix these up a bit, one massive arm could be the strong shape for example.
3-Tiny details. The nuts, bolts, colours etc. This step is best left out of the silhouette stage.
He also said that you should balance your drawings out. By this he means, draw the center line(The head, the body etc) and then draw the left and right arms at the same time for example. In order to get better proportions.
This step is all about the shape and silhouette, nothing more.
This is tougher then I imagined, but it's actually quite enjoyable. You free your mind of all the annoying details, and just focus on the shapes. It took me a good 20 or so drawings to begin loosening up. I shall continue producing these and then scan in a select few. I also plan to produce some via graphics tablet and Corel Painter too, just to experiment a little more.