Open your Downloads folder and double-click the file called something similar to Microsoft Office-Installer.pkg.If you haven't yet purchased Office, click Buy Office at the top-right corner first, and then follow the on-screen steps to make your purchase.If you don't see this option and are signed in through a business account, go to instead. This is usually your Microsoft account, but if you got Office through your employer or school, you may need to use that account info. If you're not signed in, click Sign in to sign in with the account associated with Office. X Trustworthy Source Microsoft Support Technical support and product information from Microsoft. If you haven't already done so, you'll need to install and redeem Microsoft Office before you can activate it.
