First time to post in eons and what do I do but ask a delicate and somewhat embarrassing question. Okay, here goes.

When you must make an emergency pit stop to go poo-poo (bad, I know), what are some helpful tips?

I will be bicycling the Big Island (first time ever for long-distance riding), and this subject worries me. To date, the max I've ridden is three hours, but my route provides ample bathrooms along the way, so it's not been a problem.

Thanks in advance.