to 2 liters of warm water, I add 20 drops. I stir it around with my finger. If my skin on my finger doesn't feel anything, then my colon is ok with it.
I used it to kill parasites. H2o2 is o2, and parasites are anaerobic so they die. I have passed so many crazy worms in the last couple years.
H2o2 leaves your colon aerobic for good bacteria to flourish. Before using h2o2, you really need to read up on it:)