You do this crap long enough and you make all the stupid mistakes yourself. After that, if you can get over the chagrin, mostly by not saying you've done this yourself, it's not too hard to describe it step by step. The hardest part is not leaving out any steps!
A good answer is easier with a clear question giving the make and model of everything. "The biggest problem in communication is the illusion that it has taken place." -- G. “Bernie” Shaw