What Should I Do For My 13th Birthday In September

Hi, my birthday is in early September and I don`t know what I want to do. Well I did have an idea but my cousin is going to copy me and do it her birthday is before me. So then it`s going to look like I copied her. I had my idea planned for a whole year now but I don`t know now what to do. I`m going to be 13 September 5. Please Help. Thanks
Posted by Aubrey; updated 07/12/17