Out on the playground or anywhere you have pullup bars, parallel bars for dips, and a step or block for calf raises. For the first exercise, pistols, I used to put a stool on either side of me to support me at the lowest point, since I'm trying to build up strength in an old ankle injury. Now I do the pistols up on a stool. Check out beastskills.com for the tutorial on different pistol variations to build up the skill.