What do I do about my sister?

I know this sounds like a typical problem, but I really need help. I’m 14, and my sister is 16, and she always yells at me everytime SHE has a bad day. In everything she says to me, she says it in that attitude that makes me wanna cry. This has been going on for about 3 or 4 years, so it’s not just a phase. Please, please help!