I know many parents have rules about the furniture and enforce them well, but I am not one of those parents. The only rule I can consistently enforce is "No feet on the table". Everything else is up for grabs. My kids jump on every piece of furniture I own. When they want a snack out of the cupboards they get a stool and climb up on the counter. Yep. Icky dirty feet on the counter.
They regularly watch TV upside-down on the back of the sofa. This looks like a wonderful back stretch, doesn't it?

The stairs are rolling, sliding and bumping down. Often face first. Even when they were very little.
I know. You're horrified. I am a permissive mother. Although my kids have regular bumps and bruises, they've never had broken limbs, concussions, or stitches. Not a single one. In fact, they may be less likely to get seriously injured because they have so much practice time with balancing, shifting weight, and judging their own strength. I watch them carefully, of course, but I never, ever ask them to sit still. Those wiggles are not just going to go away on their own, I figure.