Since you are suffering from brain fry, we'd better start with a few simple things....
1) -- pull a spark plug, ground it, and see if it is sparking when someone tries to start it up.
A) -- No spark. Go back up the electrical stream and start checking things like coil, power to the coil, ignition box, etc...
B) -- Spark. Re-install spark plug and confirm fuel.
2) -- Check fuel pressure and confirm the pump is working. Make sure there is fuel in the tank, don't laugh, it happens.... lol
3) -- If spark and fuel are good, confirm timing. Dizzy pointed at #1 on compression stroke? I have come across on more than one occasion where the person turned the engine until the #1 piston was at TDC -- BUT, it was at the end of the EXHAUST stroke. Thus, the dizzy was 180* out.
Is the engine spitting back, popping, or anything like that, or just cranking over with nothing else?
When your brain gets back in proper working order, let us know what simple thing it was......