Before giving a rabbit access to a room, walk through it at floor level looking specifically for chewing hazards. Cover or hide electrical cords using cord protectors or by routing them out of reach entirely, since chewed cords are both a shock and fire hazard.
Remove or block access to houseplants, checking each one against a rabbit-safe plant list, since many common varieties are toxic. Protect baseboards and furniture legs with plastic guards or furniture, since rabbits will happily chew wood trim given the chance.
Block off any small gaps behind or under furniture and appliances where a curious rabbit could get stuck. Keep small objects, books, and anything chewable up off the floor, and secure trash cans and low cabinets with anything toxic inside. Finally, provide plenty of appropriate chew toys (untreated wood, hay-based chews, cardboard) so your bunny has a satisfying, safe outlet for their natural chewing instinct.