Then scribble it down on something, keeping in mind that it will evolve. This rough draft will guide you. We decided to make the base first so using the birds eye view we shaped our wire to match the outline of the frame.
You will notice that we laid out a drawing showing approximations of length, width and angles. This was for reference. Deciding where the back and front supports go is next. These will be soldered in place. Be sure to flux the joint for a good bond. Also use a surface that will not conduct heat or burst into flame.
After the joints cool inspect and add or remove solder as needed. Add further cross supports.
Going back to the sketch (scribbles) develop a concept for the right side support.
You will notice here that we have re-drawn our sketch onto graph paper still it is not to any scale but this helps us with angles and lengths. Once the layout is complete it is soldered separately.
It is then easy to attach that side to the already formed base frame. 
Shaping the top front rail is next, we do it like most things, by eye. This view shows us trying to figure out what compound
angle looks best for the front top angle, keep in mind that it doesn't necessarily have to follow the line of the lower angled tube. In fact on the PROTO II the door opening is not only wider at the top it is also further forward than the bottom. 
The front and left side assembly is quite similar you can see that some novel front end changes have occurred compared to the original drawing. This top view shows significant c
hange from the sketch. FRITZ and HEINZ 
