I might do it in a friend's pool just to show them what SCUBA is like and to get them interested in it, but not without giving them a crash course of training first
You are not an instructor...DO NOT attempt what you stated here. Any thing happens and you can be held liable. You should know better, being that you are certified, that you are not to teach/loan any gear out to uncetified people. You can kill them in less than 4' of water.