It's easier and faster to do it with 2 people - get someone to stay in the car (provided it's stable), and push/release the brake pedal when you tell them to.
If you end up using the G2 Caliper paint, you may have to deal with the disadvantage of painting all of your calipers as once since the paint has to be used in a very short amount of time once it is activated. If that is the case (which it will be for me when I do it), you'll probably just let the entire system drain out, and then put all calipers back on and bleed them one at a time. It will take a bit longer than if you do one caliper at a time, but the process is basically the same. At least you will have a completely fresh fluid system for your brakes.
Good luck,
TRU