Ideas for self bondage?

If you plan to use something like locks or cuffs, you can freeze the keys in ice, giving you time until the ice melts. I would highly recommend using a friend for a back-up though. This person doesn't need to know the details of what you're doing, but it would be wise for someone to come by, say an hour or two after you anticipate finishing, in case something happens and you can't release yourself. Once freed, you can always call that friend later and tell them not to bother coming by for whatever reason you use. I've done a few things, but I don't recommend taking unnecessary risks. Hope this helps.