Using fresh and cold iceberg lettuce is the best way to make and keep a crispy salad! After you have washed the entire head of lettuce, save it (or any leftover portion of it) by wrapping the cut side in paper towel and storing in a gallon size zip top bag. Remove as much water as possible before storage and keep it cut side (or core side) down so it can continue to drain. It should stay fresh for up to 1 week.