Lots of great info here.
Best I can do is tell you is what not to do!
Years ago I worked with a guy who had a 'Plum Crazy' purple 340 Duster. Came to work one Monday morning and his Duster is now silver! Well, I was running a little late so didn't have time to look closely at it. I walked in and said, "Chuck, who painted your car this weekend?"
He said, "I did it on Saturday."
Not previously knowing he was a car painter, I stupidly asked him what kind of spray booth and equipment he used.
He comes back with, "Spray booth? I used the attachment on my vacuum cleaner and painted it in my driveway."
Checked it out after the workday and found he didn't remove any trim or factory decals. He taped over the black vinyl between the tail lights but didn't bother to mask over the 'Duster 340' logo.
One of the older guys I worked with stared at the car for a few minutes, then said, "Looks like you put some paint in a sock and swung it around your head."
Needless to say, the paint started peeling a couple of weeks later.