Create a macOS High Sierra Bootable USB Drive. In this video, we are going to look at how to install macOS Sierra. Download the relevant macOS or OS X installer from Apple, then use Terminal to create a USB installer you can boot up from. These links will change annually for the expected future, so please consider using Apple articles or other answers here to locate the correct links if the ones below change or are removed. Make sure you download the macOS High Sierra Installer to the /Applications folder and leave its default name. Apple now has a page up and live store links to download Sierra after High Sierra was announced.