The best ways to de-stink your stuff might not be easily available when discretion is the order of the day. If you don't want to leave a bathroom stinking, redditor RatherTall has a quick-fix concoction that he says masks the odours well when you're at someone else's place.
Here's the technique:
Fill the sink with hot water and put a small amount of shampoo, conditioner, toothpaste, mouthwash, whatever they have in the sink. You really only need a tiny amount. Splash the mixture around and let it permeate the air. Shouldn't take long.
The post adds that this makes the bathroom smell like it usually does, helping you avoid a socially embarrassing moment. And hey, you don't need anything that's not already in the bathroom, so it's easy to implement.