There have been so many articles about the troubles caused by bad gut bacteria, but hardly anything about how normal people can improve it.

This guy seems to have done both for skin bacteria.

It's worth noting that he washes hands (presumably after visiting the bathroom) and he bathes in order to remove dirt (as opposed to remove sweat)

So, if he (and this is speculation) washes hands after bowel movement, shouldn't he be washing that area regularly as well?