Before you start
This guide is general information from people who wear cages, not medical advice. Bodies differ, and if anything here does not match what yours is telling you, your body wins. Anything that hurts, goes numb or changes colour means the cage comes off, and anything that does not settle once it is off is a question for a doctor or NHS 111.
Have a way out before you lock. A spare key where you can reach it, or a lock you can open yourself, is not cheating; it is what makes the first week safe to try. A keyholder can hold the key later, once you know how the cage and your body get on.
Putting it on
Go in soft. A cool shower, or a minute with cold water, makes the first try easier, and a quiet hour at home beats a rush before work. The ring goes on first: one testicle through, then the other, then the rest. If it will not go, stop and try again in a few minutes rather than forcing it.
A little water-based lubricant on the inside of the ring and the cage helps the skin slide; silicone-based lasts longer under a silicone cage but can mark some plastics, so check what the maker says. Line the cage up with the ring, bring the two together and lock. Then stand, sit and walk for a few minutes before you call it done.
If the ring pinches or the cage pulls, take it off and look. A cage that is wrong on the first afternoon will not be right by the third day. Many people try two or three ring sizes before one fits, and that is normal, not a failure of the person.
The first night, and why you wake
You will probably wake up. Erections at night are part of normal sleep, several times a night, and a cage turns each one into a tug for a minute or two until it passes. Most people describe the first two or three nights as broken, and the week after as ordinary again.
Going to the toilet before bed, sleeping a little cooler and a glass of cold water by the bed all help some people. Lying on your side with a pillow between your knees takes the cage out of the way. If you wake in pain that does not ease within a few minutes, take the cage off and sleep: it goes back on in the morning, and the night still counts as a day you logged.
Day two: what rubs, and what to change
The second day is when a fit that felt fine for an hour shows itself. The most common rubs are the ring at the back, where it meets the skin behind the testicles, and the tip of the cage where the skin presses on the end. A red mark that fades when you press on it is normal; broken skin is not, and it means a change tonight, not tomorrow.
Three things to change, in order: the ring size (one step up is the usual answer to a pinch), the cage length (a cage that is too long moves and chafes; too short presses when you are soft), and the gap between ring and cage, which some cages set with a spacer. A thin layer of unscented barrier cream on the areas that rub helps while the fit settles.
Write it down. One line in the day's note, what rubbed and when, is worth more by the end of the week than you would think, because the fit you end up with is built from those lines.
Work, and the gym
Most people can sit, walk and work a normal day locked, and nobody can tell. Looser trousers and underwear that holds everything in place (briefs or trunks rather than boxers) make the biggest difference. Keep the first day at work short if you can, and the first long drive or train journey for the second week.
At the gym, start with what does not bounce. Weights, a walk and the rowing machine are usually fine from the first week; running and cycling are worth a short trial first, and a saddle may need a different cage or a different week. Shower afterwards and dry properly, because sweat under a ring is what makes the skin sore.
The toilet is the question everybody has and nobody asks. Sitting down is easier than standing for the first weeks, and a quick rinse or a wipe afterwards keeps things clean. It becomes unremarkable faster than you expect.
The signs that mean off now
Pain that does not ease within a few minutes. Numbness or pins and needles anywhere below the ring. Skin turning pale, blue or very dark. Swelling, broken skin, or any sign of infection such as heat, spreading redness or discharge. Any of these means the cage comes off straight away, whatever day it is and whatever you agreed with anybody.
If it settles quickly once the cage is off, rest a day and look again at the fit. If it does not settle, or you cannot get the cage off, that is a doctor or an emergency department, and there is nothing to be embarrassed about: they have seen it before. Stopping early is not failing; the days you logged stay yours, and the next lock starts when you are ready.
A first week is for learning how the cage and your body get on. Change the fit, write down what you notice, and take it off the moment it needs to come off.
All the best, Erik