I like to draw my new designs before making any sort of a mock up or prototype. Below is a drawing of a chair that I designed in 2001. I start with a basic idea for the design and then draw a stick chair version of all of the simple parts, such as the leg angles etc... By projecting the front, side and top view, I can plot points and see exactly what the results will yield.
I normally start with the shape and size of the seat that I am interested in and then down to the legs. By using the tables devised by Dave Sawyer in Drew Langsners book, I can easily get the resultant and sighting angles for my pattern.
Learning to do this kind of projected drawing is not as tough as it may look. You start by arranging the page (graph paper is essential) so that the top view will fit directly above the front view and so that the side view will fit directly to the right of the front view. The key is the 45 degree line that acts to link the top and the side view. For example, draw a vertical line from the front of the seat in the side view all the way to the diagonal line. Then draw a hortizontal line from that point on the diagonal across to the top view. This will show where the front of the seat is when viewed from above.
Often, in designing, I switch back and forth from view to view as I arrive at what looks best. Obviously, the top view will be very important as you proceed to make a seat pattern, but I find that it is best arrived at by working the other views first.
After my stick chair drawing is complete, I'll often draw in some of the aesthetic details that will give the chair much of its character. This can inpire me even more to want see the chair in wood. While drawing is a good start and a great way to save a lot of fiddling around, more often than not, the actual chair calls for more than a few refinements.
To learn how to do this kind of projection, I suggest starting with a simple object, such as a brick, and work your way toward more the complex. Once you get your head into it, you'll start thinking in 3 views!