Pull off the pedal cranks, fold down the bars, pull the front wheel, maybe pull the seat.
Once you do all that mopeds get really small. I fit a Hobbit and a half in my Toyota Paseo using that method and that is a TINY car.
One thing to keep in mind is to drain the gas and put a tarp and or blanket down so you don't cess up your car.
I also like to put either mittens or winter socks on the forks and the handle bars grips so they don't fuck anything up.
If grips touch your roof they fuck it up. They divot the foam and leave these nasty black marks.
And the bottom of forks can scratch the shit out of your paint or damage your upholstery.