Things I Find Work Well.I have always done self-gunging, and i have always tried to keep it secret. Once I made a mixture of routine ingredients, eggs, sauce, and jellies. That stunk up the tub though, so I've tried different things have have found some that are easily cleaned and still make a good mess.
I wear nylon or mesh clothing, as it is easily cleaned and can still be wearable after a wash. not to mention is feels good.
The first substance I use is maple syrup. It gives a sticky/slippery feel, which is fun to use and pour on yourself. It washes down the drain easily, and only leaves a little scent.
The second thing I use would be soda. It sounds weird, but after the cold shock the carbonation slowly tingles on you, even through your clothes.
Another thing is melted Popsicle. The tube Popsicles, like flavored ice. I simply don't freeze them, and use them when I feel like it. Flavored ice is completely a liquid, so it drains easily too.
One of the things I like most to use as gunge is shampoo. I use a simple store brand, with no added ingredients like menthol. I like it not just because of its texture, which is slippery and sensual, but also because of the quantity. You can use an entire bottle for gunging, and nobody would suspect a thing except that you used a little extra of it.
I have not been caught yet, so I believe these work. So almost every chance, I decide to have a little fun.