The easiest thing for you to do would be exchanging the ETH for BTC on sites like Yobit, Livecoin, Hitbtc etc.. If the amount is large then I won't suggest you to use Hitbtc since there were recent complaints about withdrawing and losing assets on Hitbtc. You could use Yobit as it doesn't need any sort of ID verification for withdrawal. There is a minimum limit of 0.05 ETH to be deposited on Yobit and I guess you will be having more than that. If you do the transfer within today and exchange it to BTC then you can get free Super Bitcoin as the fork is tomorrow.
Link : www.yobit.net