I have a small C (21ft) - other than inside space (I have a bit more than a B), most things are pretty similar. Few things I've learned:
Keep it simple and keep things in their place - the less you have to move things around to do everyday things, the better. It makes it easier to drive out to dinner or sightseeing if you don't have to spend an hour battening down everything. It also makes it easier to arrive late at night and go right to bed if you don't have to rearrange a bunch of stuff off the bed.
Packing cubes - these work great for storing a variety of things. Electrical cords and adapters, water hoses, clothing, junk drawer items, toiletries, etc. Color code for easy identification. You can fit more in the cupboards and they stay organized. Utilize the different sizes. I use the smallest for usb cords, earphones, etc., large for extension cord, etc., and so on.
Simple outdoor living - because you'll be taking your home with you when you sightsee (making it clear that you're gone), keep your outdoor stuff to the minimum and easily portable. If you feel secure with the campground/park, you can leave it in the site while you go out - but if you don't feel secure, you can easily load it up for a day trip.
Re-evaluate your supplies every year - If you haven't used it in the past year, get rid of it. This will help keep things from getting over crowded. Don't stock up on gear for "just in case", "if someone joins us", and so on. If you know someone is joining you, bring disposable products to supplement for THAT trip.
Be as self-contained as possible - full hookups are great, but learning to go without can simplify things. Not having to unhook sewer/power/water/cable/etc., each time you want to go someplace is easier. Plug in when needed - not by default. Hook up sewer WHEN you need to dump not every time you park.
1975 American Clipper RV with Dodge 360 (photo in profile)
1998 American Clipper Fold n Roll Folding Trailer
Both born in Morgan Hill, CA to Irv Perch (Daddy of the Aristocrat trailers)