Start by wearing a diaper and a pull-up (the kind which you can’t just rip off), leggings (or the tightest pair of shorts you dare to wear in public), a short shirt and no belt. Bring a small lock with a single key with you and go to the nearest mall. Hide the key at a place far away from the mall bathroom and go to the bathroom. Now you will get yourself into a nice little predicament: make sure that you have to mess, either by enema or suppository and then use a thin chain (don’t make it to visible) to chain your ankles together. Now you can’t take your pants off completely anymore and therefore can’t really remove the pull-up. Now waddle over to your key and hope you’re fast enough ^^
The suppositories and the missing belt should make hiding your secret a hard task
Enjoy!
Please read my likes/limits before daring me, obviously public is no limit for this dare.