Also on the wood ones, drill a wrist loop hole through the bottom
of the handle and sling a short piece of parachute cord through
it for safety. When you get tired, it is easy to let go of the
handle, and you don't want it flying off at someone.

A file will be needed to sharpen it. The coarse serrations left
by it will help in the slicing motion of the tool. A grinding wheel
is useful for the first sharpening.

Use a pulling motion as you swing for efficiency.