From the book "The Witch's Circle" by Maria Kay Simms
It is best to use a branch that has fallen off a tree.
If you must take a branch from a living tree, you should do so respectfully. Ask the spirit of the tree for its gift, tie off the place to be cut with a red cord, score it with the bolline, and pass the bolline through the complete cut after the sawing is done. Afterward, thank the tree and give it a gift of water. The branch will need to be thoroughly dry before it can be made into a wand.
The wood is first cut to an appropriate length.
The traditional length is from elbow to fingers, though as with
most other things, this rule is not absolute. Some people like
them longer, and some petite. After a thorough sanding, oil the
wood to bring out the grain. A favorite embellishment is to mount
a crystal point in the top end. You would do this by making a
hole in the top with a power drill, insert the crystal, and
secure it with epoxy. From there you can decorate according to
the natural lines of the wood, perhaps mounting smaller stones
and crystals in the hollows. Symbols or runes can be added with
wood burning tools.