My first tip is "No Fear". I'm a 50 year old office worker with zero mechanical apptitude. Before i got into pinball, my tool chest consisted of a couple screwdrivers and a hammer in the junk drawer in the kitchen. One year and 5 machines later (all non-working brought to life)...well, sometimes I still get a little apprehensive when approaching a new problem...but like most things, once I dive in I find the worrying was worse than the fixing.

I really think this is the key, and is probably somewhat related to the "success" I have enjoyed so far. My style of thinking is heavily analytical, somewhat linear - and that really helps in this hobby. Every machine has a logic - and too many people spend too much time chasing problems with methods that are, for lack of a better word, illogical. Keep it simple, isolate the problem down to the basics and go from there. Simple things like "this XXX needs voltage to work...am I actually seeing the voltage there?"

Finally, when stumped (I know squat about diagnosing board level problems, but I can replace components), turn to places like these for help. But again, the best help will come when you can clearly describe the problem and you have already isolated it down to the most basic level possible.

But ultimately, you just gotta jump in. In the best Rob Schneider voice from "Waterboy"...."You can do it"!