Open the bottom of the bag over the toilet. For feces, you can gently squeeze it out of the bag; urine will automatically flow from the bag when it is opened.
[header] How to change a colostomy bag [title] Start by emptying your colostomy bag. [step] If there is urine or feces in your colostomy bag, it is important to empty these prior to changing the bag. The best place to do this is in the bathroom.