I am pretty challenged when it comes to electrical too. My 1st scooter didn't have a spark so I read the forum, got a cheap $20 multimeter at WalMart, and started testing the wiring. Long story short, I concluded you need a fairly expensive multimeter to do the testing, probably several $100's. Basically, my multimeter told me everything was bad, except for the coil. After that experience, I still don't know very much about electrical.
The battery was dead (don't need a tester to figure that one out), but the advice said it should run without battery. I finally bought a new battery and everything started working, amazing. Your problem is probably very simple, like a corroded connection. May just need to unplug a connection and plug it back, I don't know. I guess if you know how to use a tester, you could zero in on the bad connection, but I am like you I guess, not that easy IMO. Good luck, if you keep at it, you will get it fixed eventually.