So you're going to share a hotel room with a buddy or a few friends.
First of all, if your friends are close enough to you to share a room, y'all are close enough to discuss your colostomy, and its potential issues. Do it.
So you have to do a bag change. Many hotel rooms have sealed windows, many of the bathroom fans are useless. Here are the hotel tricks:
1) Let your friends know all about your bag, be last in the shower as they go down to breakfast, and if you're somewhere safe, prop the door to to the hall open at least as long as you're in there.
2) Try to get a room with a balcony--lots of ventilation for late-nite bag changes!
3) My BEST TRICK! Check in. Excuse yourself from your friends, and ride the elevator to the basement. There WILL be a bathroom there (often beside the gym). With no traffic.
So, during the course of your stay, dash out for a bag change in the basement bathroom via the elevator, desk staff will never see you, friends know that you are working with a colostomy and need to chill.
I hope this helps for "Tips"!