The first line of defense against mice is to seal your home. Any holes that are larger than ¼ inch will allow mice to gain access because their jaws can fit into tight spaces like these and quickly chew larger openings that allow them to enter a building. Therefore it is important to seal all openings with steel wool or caulk.
Be careful not to attract mice with food – where possible, store food in plastic or metal containers. Regularly clean under stoves, refrigerators and cupboards.