I carry IWB at about 4 O'clock and have every day for 21 years. I undo my belt and pants, then grasp the weapon and my pants with my thumb inside my underwear. I lower the whole works as I sit down. Once my pants are all the way down I move my right thumb up and over the back of the weapon. This hooks my underwear over the grip holding it securely in place while also completely covering it so it cannot be seen through the stall gaps or by nosy kids. When I'm done with my business I do the exact reverse. With this method the weapon stays holstered, it can't be seen by anyone else, it is ready for action if needed, and there is no extra effort or motion other than the move to hook/unhook the underwear over the grip. Try this at home, it works flawlessly and very quickly becomes "automatic".
If I'm going commando I still use the same means of lowering/raising my pants holding the weapon and my pants. I fasten the top button of my pants once they are down and spread my knees slightly to keep the weapon in place against my leg.
I highly recommend trying and perfecting this or any other method at home. Like all things weapons related I do the exact same motion every time whether I'm at home, someone else's house, or in a public restroom.
