The phrase "wear something on one's sleeve" means to openly display or show your emotions or thoughts to others. Some synonyms for this phrase include "show one's true colors," "let your guard down," "be transparent," "be forthright," "be candid," and "be sincere." If you wear your heart on your sleeve, you make yourself vulnerable and open to judgment from others. It's important to be aware of the consequences of showing your emotions and thoughts too openly, but it can also lead to genuine connections and understanding with others. Ultimately, wearing something on your sleeve is a personal choice and reflects your level of comfort with vulnerability.