Going around a neighborhood or some other place with a lot of cars late at night, preferably 1-3am, and seeing if the cars are unlocked. If they are, search for GPSs, stereos, iPods/phones, or other items worth value. Favored spots are hotels(travelers need cash and GPSs), amusement parks(Kings Island/Holiday World, they need GPSs and cash too
If you set an alarm off, run and hide between houses, hop fences, do anything you can to get away. If you have a feeling you arent going to get away, ditch the items somewhere the cops/civis wont find, and wont get ruined. So when you get caught, you wont have anything on you.
After you collect enough valuables, Id recommend waiting about 3-5 weeks, and then pawning the items.
Dont do too many items at one place, and switch up pawn shops, its smarter to not get caught.
* These videos are coming directly from Youtube, they may or may not be most relevant to the word "Car hop"