Im quite self concious of my bottom lol?

okay i have quite a pear shaped figure so i'd say my bottom is quite big.. i even get called "ghetto " because of it hahha. i dont mind my bottom when im wearing clothes its just when im in my swimming costume. im going on holiday in late july and i was wondering if there was anything that i could do to tone up that area? because although i like my bum the reason that i am self concious is because it wobbles when i walk and i have a bit of celluite which is noticeable depending on the light.. i want to be able to run around the swimming pool in the summer without having to worry about what is wobbling and what isnt, any advice? im 15 years old btw. no harsh comments please thankyou xx