I'm no expert either but I have painted about a dozen cars in my 55 years.

As others have said, I do the jambs and other areas first and then mask them off to do the outside.

I start at one side of the roof and paint toward the middle, then go to the other side of the car and paint from the middle of the roof to the side.

Then I start at one side of the hood and do the same thing.

Then down the side of the car that I just finished the hood on, over the trunk, and up the other side of the car.

Seems to give the fewest breaks in paint.

Others will likely have other ways but this seems to have worked for me pretty well.

Thanks,
Ken