Selecting the right bow
A fairly large number of instructors recommend bow lengths that, I feel, are entirely too short. Why anyone would use a bow that is 18"-24" I simply do not understand. The purpose of the bow is to spin the drill as effortlessly as possible. (Most beginner's arms will wear out from fatigue long before they ever get their first ember glowing.) I have watched many instructors, demonstrating  on instructional videos, using "shorty" bows, literally wear themselves out. It's totally unneccessary, awkward, and going against the laws of physics. I will show you how to use a longer bow successfully without nearly the strain. I have had many 10-12 year olds weighing less than 90 pounds succeed using these techniques. So, pay close attention and follow along.
Length: 32"-36"   Diameter: finger width    Flexbility: fairly rigid      Shape: slight C-curve
Next: making the Bow