"Kicked up one's heels" is a colloquial expression that denotes having a great time or letting loose and having fun. There are several synonyms that can be used in place of this phrase, such as "let your hair down," "cut loose," "live it up," "carouse," and "party hard." Each of these phrases can express the act of having a joyful and playful time with friends or family, which causes one to enjoy the moment and release any inner tension. These phrases are perfect to use when describing a happy occasion or celebration, such as a birthday party or a wedding dance.