This question crops up here on GT every now and then. The most foolproof method for #2 carry is to keep the piece inside the crotch of your underwear. Secure, invisible from outside the stall and not too easy to forget.
Rust and bureaucrats. Freedom and vigilance. Front sight and trigger. Kindness and firepower. Situational awareness and tolerance. Safety and concealment. Taxes and allegiance. Love of man and surgical marksmanship. Once a soldier, always a soldier.