How to convince parents to let me do something?

I'm 13 and I have an older sister that is 15 and she's so perfect and everyhing. She didn't ask for things until later like to get her ears pierced, for a facebook, to get a phone, to go on mission trips. And now my parents are using her as an example and are like your older sister didn't get a phone until highschool or your sister didn't get her ears pierced until she was 15. You get the idea. Now I can't get pratcially anythig! What should I say or to to try to persuade them?