Although I know about the marshmallow trick and have used it in a pinch...even after an evening meal when there is a leak, I try to do my changes without because of the crap in the ingredients. We each have our "quiet times" except for urostomates. If I can, I change then, if not, I always keep some folded up toilet paper at hand while changing. Having the whole change ready at hand ahead of time helps a lot too. Standing at the bathroom sink while getting stuff ready in case of eruptions . I have even found that having the "intention" of a quiet stoma helps. Sounds strange but it seems to work most of the time. Most of all, not getting too stressed out about it is best.
Carrying a couple of paper towels in my purse "just in case" for damage control while out is a must. Fortunately, that has only been an issue twice in 2 1/2 years.
Using a flat bedsheet folded up like a draw sheet on my bed for night time accidents saves on changing the whole bed.
Just some practical tips.