Well... if you're a good candidate for reversal, 4 to 6 months is the usual time frame. You could get one later than that if your situation requires it.
A stoma is pretty tough. A mild bump won't hurt it. Just be careful the first couple of months... until your mind always knows it's there.
Bags are tough, unlikely you'll pop it. When I first got my colostomy, I was so careful around my stoma. Wouldn't get it wet. Was cautious touching the bag and wafer.
Now it's 17 months since my surgery. I take the wafer and bag off and shower with the stoma hanging out. Water and soap won't hurt it. But... do NOT use soap that contains fragrance, lotions, or dyes. Those chemicals will interfere with wafer adhesive. I use Cetaphil soap.
You can gently wipe off your stoma with a wet paper towel. Great for cleaning poop bits off your stoma in the shower. Do NOT use tissue paper.
You'll get used to your stoma. In the meantime, read/research all you can about reversal. Especially think about your situation. Why you got the ileostomy. There are many success stories on the internet. And some unsuccessful tales. Learn all you can to make an informed choice.