1. Choose something to draw
2. Look only at the contour line around the thing
3. Place your pencil or other media on the paper
4. Without taking your eyes off the object or looking at your paper draw all the way around the object
If you do this often you will be amazed to see how your blind contour skills can improve. The picture on the left is from the beginning of my practice and the picture on the right is later on. It is fun and interesting to see the changes.