Firstly, the rubber feet of a ladder will largely grab that rough driveway surface. However, for a more secure footing, use rope. The steel tracks of the doors will be strong enough to hold the ladder from sliding. Set your ladder up where you need it placed. Then take two ropes, tie one around the base of each of the door tracks, then tie each one around the corresponding side rail of the ladder just below the first rung. For the center, you could just rope around the center column between the two doors. Pull the rope enough to pick up any slack. Between the grab of the feet and the rope preventing sliding, you'll have no problem. Your options are to rent scaffolding, cheaper than a boom, with some adjustable feet. Or, use two 24' ladders, some ladder jacks, and an aluminum pick, all of which you can rent. A pick is an aluminum stage of varying widths and lengths. If you're not comfortable climbing or standing/working on a one foot wide plank, get the scaffold. Take your picture to an equipment rental place and ask them to recommend staging that will work, bring your height requirements and the width of the level area of the driveway. Ask if you could use Baker scaffold (a smaller, narrower scaffold type) if you tie it into the center column of garage. You could put that up the center and flank off each side with smaller planks, ladders and jacks and bring it down all the way cross at the same time. But I didn't tell you any of this, lol.
