This is evolving into advice for hiking. But that's okay. I still go hiking, even though I don't often get very far out of town. It's the cost of gas, you know.
Although I still have a "no-backup" (that is, a no cover-up) on my list of things to do, I hike nude when it is possible and practical, which isn't that much, unfortunately. I generally carry a small pack with a few things all the time, mainly to keep in practice for long hikes. I'm not sure if I really need to carry anything at all and sometimes I carry only what fits into my pockets. But for the long hikes, nude or not, this is what I carry:
Water, poncho, a little 1st aid kit, some toilet paper, something to eat, sometimes a map and compass, and a sort of emergency pouch. In cold weather I'll carry coffee in a thermos and a mug and still a little water. I also carry a small plastic trash bag, a small plastic bag for trash and a ground cloth (a square of plastic) and foam pad (for sitting on and to stiffen the frameless pack). If I expect rain, I also carry an umbrella. If I am planning to hike nude, I leave the car already nude but with something to wear in the pack. Sometimes I don't take enough to wear, to be honest.
I used to carry a more or less complete 1st aid kit. Everything you read says to, so I did. But having done so for 40 years, I decided that what I carried wasn't adequate for a real emergency and was mostly unnecessary for what it was good for. I still carry something, though, but only an army field dressing and a selection of band-aids, mostly large. I figured that the worst thing that could happen that I could treat myself with what I could carry was a serious cut or puncture wound, so that's what I attempted to prepare for. A bad fall resulting in a broken bone would probably be a lot worse but I don't know what you might carry for that. Anyway, my so-called first aid kit is about the size of a pack of cards.
That so-called emergency pouch that now forms part of my "always carry" outfit contains a candle, small flashlight, matches, a food bar, a knife, fork and spoon set and maybe something else. Don't remember and I'm not going to go downstairs to check. I had this zippered pouch that I thought was perfect for making up this emergency kit and that's about what would fit inside. That's the most of a survival kit I've ever put together and I only did that last year. In about fifty years of tramping through woods, parks, canal towpaths and strip mines, I think I've used a couple of band-aids and that's about it for "emergencies." But if I didn't take anything, I'm sure I'd need something and desperately.
I still take the regular 1st aid kit when travelling and for overnights. Aspirin is sometimes used.
Reading back over this, I note that I have simplified things fairly well but what I miss or have lost are the spontaneous hikes from my younger days when I took none of that stuff, sometimes even leaving the clothes behind.