I don't know the exact expression or word to say that in English. But "tirar onda" is to try to raise your status in front of other people by showing something good you have or saying something important you done. For example: you just bought your new car and you imediately drive your car to your friends homes to show it and say their qualities. Or you are the best pupil in a class and you say to everyone you are the best. Or, when your football team wins a match or championship, you say to everyone who like other teams the your is the best. When you do these actions, you are "tirando onda".

Some have asked for an English equivalent phrase. For "raising your status in front of others," "tirar onda" is close to "putting on airs" or (in slang) "to front" or "frontin'" From UrbanDictionary.com: "Urban slang. To put up a facade or make appearances, typically to impress or in some way deceive to maintain image. From 'to front'."

In Brazil, "tirar onda (da cara de alguém)" means to poke fun at/kid someone. For example: A: Sério? (Really?) B: Nada! Só tirando onda (da sua cara)! (Nah! Just poking fun/kidding.) It can also mean " to shit someone": A: Tá me tirando, mano!? (You shitting me, bro!?) *Just use "tá me tirando" (="está tirando onda da minha cara") B: Foi mal, mano! (My bad, bro!)

Actually, Luciano's answer is not right. "Tirar onda" is an informal commonly used phrase meaning that somebody is flirting wlirting with you, or somebody else. What Luciano explains will be more like "presumir", showing off in english.

i dont get the meaning, sorry.