If you really want to try i will advise your to put a lot of cream and powder when diapering yourself , and maybe to put cream on your diaper-area during several day before it , to prepare your skin for the harsh treatment you are going to impose to it.
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I will also advise your to eat properly , regulating your fecal PH is very importante ( Healthy ph is basic, if you have an acidic PH diaper rash would be inevitable). Basic PH is also very violent on the long run, and your idea to wear it for so long will probably cause it to interact largely enough with your skin
To keep a neutral or slightly alkaline PH try to not eat to much fat , eat vegetables and drink a little bit of lemon juice during the 3 day preceding your experience ( it may seems weird but an internal action in your body will make your stool less acidic ).