Vol I is the way to start. That will allow you to learn to make a functional bow (though not overnight, by any means). After that, Vol 4 is actually the next most important and useful, as they revisit several areas where another decade plus of experience and learning have helped. Vols 2 and 3 are interesting, but mostly very specific esoteric subjects about certain types of archery throughout history. Well worth getting and learning, but much more limited in scope. Highly recommend start with I, progress to IV, then fill in the other two. That said, Vol III does have a very good chapter on tools, their selection, and uses, but I and IV are more valuable.