Closest thing I’ve seen to a how-to for the infamous Mentos and Diet Coke bloat:
“Diet Coke and Mint mentos are the best for a soda bloat. I’ve tried it with the different flavors of mentos as well as different sodas. It actually doesn’t take very many candies or alot of soda to achieve results. If you’ve never done it, start small in small amounts. The key to remember is that stomach acid stops the quick reaction as well as a bellyful of “decarbonized” soda, so after the first liter or so, any belly expansion is the result of the liquid itself and not the mentos.
"That said, don’t chew the candy. Its the surface of the candy that causes the dissolved gases to release, as well as the lining of your throat and stomach. We’ve all experienced that from chugging it alone.
"Unwrap a roll and get several candies ready. Open your can, or liter bottle, and take a few sips. Then swallow one candy, and chase with a few fast gulps of soda. Repeat. And Repeat. And.. I think you can figure it out from there. I’ve found 8 candies and 2 cans of ice cold diet coke are just right."