The phrase "keeps your shirt on" is often used as a way to tell someone to calm down or be patient. However, there are several other equally effective synonyms that you can use instead, such as "keep your cool," "remain composed," "have patience," or "stay calm." Other options include "keep a lid on it," "hold your horses," and "keep your temper in check." Whatever the situation may be, there is always a suitable alternative to convey the same message. By using such alternative phrases, you can avoid monotony and add a touch of creativity to your conversations.