Can someone please help me out with this picture challenge?

Below is a link to a picture puzzle that I need help with. The challenge is that you need to draw the entire figure without taking your pen/pencil off of the paper, and you cannot draw over a line more than once. The link has every line color coded with the directions L (left) and R (right). Please tell me where to start with this picture, and where to go from there, in order to complete the challenge. I would suggest saying something similar to this: 1) Start at Green, and go left to right, 2) Go to Black, go right to left, and so on. A lot of people that tried to do this puzzle could not figure it out, but I really want to know how to do it. Someone told me that it is possible. Here is the link:

http://dl.dropbox.com/u/15394940/Drawing.JPG