Google is a good friend, but remember to cast everything in a skeptical light if it's trying to sell you a product, especially one with risks or side effects of any sort.
The most important thing to do is learn, I neglected this for many years because my condition was controllable for a long time, but there are a lot of small things that effect your bowel behavior and what you think are flare ups might be foods your eating or stress induced.
Some basics are things like keeping a food log and looking at it any time you have issues. Remember that diarrhea is not necessarily the food you ate 7 hours ago finally passing, it can be a food you JUST ATE causing rapid bowel contractions, this caused me confusion for a long time. Other symptoms can be similarly quickly developed from food you just ate, and sometimes it may be that food you ate 7 hours ago. Keeping a log will help you to see trends. You can download calendar programs online that make this much easier to track.
If you don't already one of the first things to do that my nutritionist recommended me was to pick up a simple adult multi-vitamin like Centrum, Crohns already can cause an issue with mal absorption so throwing some much needed vitamins down the pipe is absolutely helpful.
If it's a serious issue and really hurting your day talk to your doctor about trying new or stronger medications.