Some rules are meant to be broken. Here, Katrina Stumbos, an interior designer in Sacramento, Calif., debunks the top four bathroom decorating commandments (who made these things up, anyway?). “Just have fun, and you can’t go wrong,” she says. “The bathroom is a good place to test your creativity.”

Rule #1: Bold colors make small spaces seem smaller.

Why you should break it: “For some reason, people were told to avoid dark colors in small spaces, but the bathroom’s actually the perfect place to go bold,” Stumbos says about bathroom paint. “You can have fun with color because you’re not making the commitment you would in a larger space like the living room.” Splash rich navy, loud pink or daring green on the walls—and consider buying an extra can for the ceiling. “Who says they have to be white? I’ve done stripes and pearlescent paint on the ceiling,” she says.

Rule #2: Never use wallpaper in a bathroom.

Why you should break it: First things first: Yes, many types of standard wallpaper will eventually bubble and peel in a steamy bathroom, so save them for your powder room—not your master. In larger baths with a tub or shower stall, use commercial-grade wallpaper that can withstand heat and moisture.

Rule #3: Fine art has no place near a toilet.

Why you should break it: The average American spends an hour a day in the bathroom primping, bathing and, well, you know. Why shouldn’t you look at something beautiful while you’re in there? “I’m an art collector, and I think art in a bathroom is completely acceptable,” Stumbos says. So that big, blank, windowless wall above your tub? Hang up something special to give it unexpected pop.

Rule #4: All the tile in your house should match.

Why you should break it: Your bathroom has a different look and purpose than your kitchen, so there’s no reason they should wear the same finish. Run extra-large tile across the floor and up the shower stall (be sure to go with a textured material to help prevent slips), or a dramatic glass-tile backsplash behind the sink.