How do I let my parents let me buy UGGs?

I have 2 pairs of UGGS and I love them. I wear them everywhere. Where I live it gets super cold and snowy and these are perfect. But buy them big because if you still live with your parents you have to be young. (I think) But I would get them and get them big. Tell them that they are perfect because you can wear them almost anywhere and you earned the money. If you need to tell them you will spend your money how you want and they can spend there money as they wish. Tell them I would love to hear why you think I should not get them. But I am going to. They're kinda like an investment. I hope I could help! (If you get stuck with replicas don't do payless!!!)