There are plenty of reasons to make your own magical implements:
1. It teaches you new things, such as metal engraving and carving.
2. The astral forces that taint it are localized.
Making a staff sufficient for magical purposes could be as follows (this is only an example):
1. Find an old tree, at least a centries growth and acquire one of it's larger limbs
due to age. The age and beauty of the tree imbues it with certain virtue, especially
if it has had beholders (those who see it) whose thoughts then perfume the tree.
2. Shave it. Create a conventional water of exorcism, using clear water (prefferably from
a stream due to it's purity or bottled, unlike treated tap water) and crush fragrant flowers
therein, recite the exorcism over the salt and cast it into the water and mix it in.
3. Then clean it with this water of exorcism.
This creates a perfect physical conduit for extra physical forces and hence
a magical staff. Consecrate it by dedicating it solely for magical purposes and
store it in your altar or other cabinet, closet, &c. The dedicatiion is performed mentally
then recited orally. It is to aid in the efficacy of the consecration which is merely the
dedication of the item to avoid it becoming tainted.