The phrase "let it all hang out" is often used to describe a situation where someone exposes their true feelings or behaviors without inhibition or restraint. There are a number of synonyms that can be used to convey a similar sense of candidness or openness, including "bare one's soul," "lay it on the line," "spill one's guts," and "vent one's spleen." Other phrases that come to mind include "hold nothing back," "speak one's mind," and "let the chips fall where they may." Ultimately, these expressions all suggest an abandonment of pretense or self-consciousness, and a willingness to express oneself truthfully and authentically.