Block up your mouse holes? Gaps around pipes, broken air-bricks and ill-fitting doors will all let mice through.
Kill them with kindness, with a bait of mouse killer. Some brands send them to sleep before they die.
If mice persist, call your local Environmental Health officer or a pest control company.
If you use standard snap traps, don't fall for the old cartoon cliche of baiting them with cheese. Use small pieces of peanut butter, nut chocolate or cooked bacon instead; mice seem particularly fond of them.
