While established campgrounds often have restrooms for use, there are plenty of places to camp where such luxuries are not available. Get an old folding chair with fabric seats and cut out a circle in the seat to make things easier. Then, you can tie a toilet seat on with zip ties and place a plastic bag under it: instant porta-potty! If you don't have access to an old chair like that, try a 5-gallon bucket lined with a bag and a pool noodle placed around the rim for cushioning.