One thing to do is simply leave the room or the house for a while, until you cool down. My daughter likes to go off on a long bike ride when her brother gets to her. Another is to use the various behavioral tricks to calm down, such as blowing out candles or the proverbial counting to ten. Another is to decide that what he has done does not matter in the long run and ignore him. Another is simply do not respond. Just look at him once and go back to what you are doing. Finally, you might talk to your parents and ask if they can find you an anger management class of some sort. Unfortunately for older siblings, especially daughters, little brothers are born to be annoying little brats. I think it is genetic. Fortunately, a lot of them grow up into decent people who are always willing to fix your car or mow your lawn or be your kids’ favorite uncle.