2 ways to do IMHO:
1) write simple concise rules with a few precautions, that are probably not enough to cover all cases, but help to get you covered.
2) write extensive rules that nobody will follow.
In all cases :
- get first help training for all people, and equipment ready (defib, eye wash, ....)
- don't be shy to put enough protections (emergancy cutoffs, 30mA differential, gloves, googles, protected bananas....)
- put a medical examination mandatory for every electrisation, however light.
- always require 2 persons present to do work.