You can use an online wallet to keep your cryptocurrency in and if you have purchased a miner you will may have already set up a MetaMask Etherium wallet. However for added security and so as not to be 100% dependent on internet security protocols we recommend you purchase a hard wallet. This is a physical device that you use to connect to the blockchain and in which your coins reside. These devices are pricey however they offer considerable security. We chose and would recommend Trezor wallet devices from trezor.io. Devices take a couple of weeks to arrive. Let us know if you need any help setting up.