This can give you a 90s vibe, especially if you pair your outfit with loose, wavy hair and chunky accessories. If you're searching for a casual way to wear mule sandals or heeled mules, you'll want to keep the rest of your outfit loose. Need to update your style in a hurry before you dash out the door? Sliding on a pair of mules is a simple way to give your outfit a unique look before you step out for a lunch on the go or a fun night on the town.