I woke up one day and realized I've got a LOT of extension cords.
One 100-footer (I think) and it gets rolled up on an inexpensive Home Depot cord real. I used it for years at my swap meet for the PA equipment. Never failed, the cord always came off it very nicely.
I think I've got a 50 footer the same way. I rarely use them now, but maybe once a year they make an appearance for something.
The rest of mine are 25 feet, with a couple 8-footers for running electric drills (8-10 feet seems to be perfect for running a drill).
I just loop them into coils. Do NOT twist them over your elbow/wrist, because it twists the cord.
I've heard of looping them in coils referred to as "stage loops." I guess maybe stage production companies loop them like that? Anyway, it doesn't twist the coils, so it stretches out nice and easy.
Then I hang them on the pegboard, using large curved hooks.
I have a curved hook next to every other outlet in my shop, and hang a cord next to it so it's right there when I need it.
The others I have hanging on the wall in a straight vertical line. One hook with a cord on it, next hook about 8 inches above the first with cord on it, overlapping the cord below it, and so on. I have four or five hanging on the wall that way, taking up the least amount of space. When I need one, I just grab the top one, which uncovers the next.
-Brad