You update through the Mac App Store. It is a free download from there.
First, check to make sure your Mac is compatible. If you haven't received any notices about updating, then it may be because your Mac is too old. Check https://support.apple.com/en-us/HT201475
Then run the App Store app, search for Sierra, and get it.
You update through the Mac App Store. It is a free download from there.
First, check to make sure your Mac is compatible. If you haven't received any notices about updating, then it may be because your Mac is too old. Check https://support.apple.com/en-us/HT201475
Then run the App Store app, search for Sierra, and get it.