"Tooting one's own horn" is an idiom that refers to boasting about oneself or one's accomplishments. If you're looking for synonyms for this phrase, there are a number of options to choose from. Some common alternatives include "bragging," "boasting," "showing off," "flaunting," "blowing one's trumpet," and "patting oneself on the back." Other possibilities might include "singing one's own praises," "promoting oneself," "highlighting one's achievements," "emphasizing one's successes," or "talking oneself up." Depending on the context and tone of the situation, some of these synonyms may be more appropriate than others.