Getting foot massages are a popular activity in China; friends will often go together for fun. But note, they aren't relaxing and pleasant experiences per se. Rather, it's believed that different parts of the feet correspond to different parts of the body, and foot massage is aimed at treating those different body parts. If you're not used to it, it can be painful. In any case, expect to have your feet soaked in hot water for a few minutes while the masseuse massages your neck and shoulders. Then, the massuse will apply cream to one foot at a time, and apply pressure and knead different key points. Feel free to tell them to lighten up if you find it too painful. Tea is usually served, and some places offer snacks as well. P.S. Yes you should tip.