Only leave the USB stick you’ll use during the process connected. Disconnect all the other external storage devices you don’t need during this process. If you don’t have a DVD driver to connect to your Mac, you’ll need a USB stick with at least 5GB of available space.Follow the instructions to save the ISO file to your Mac, and you’ll be using it shortly in the following steps. The first thing you’ll want to do is download the official ISO file of Windows 10 through Microsoft official webpage.You’ll use the included “Boot Camp Assistant” to do this, and the progress is relatively straightforward if you follow all the steps carefully.