I inspect the place for potential hazards and secure any dangerous items or substances, I maintain the pet's regular schedule for feeding/walks/playtime, I ensure fences and gates are secure and supervise pets when they're outside, I regularly check for any change in pet's behavior, energy level or appetit, I would offer toys and activities to keep him/her engaged, I'd stay in touch with the owner to provide updates and address any concern, I'd figure out the location of nearest vet and have an emergency place in mind.