MacMost Q&A Forum • View All Forum Questions • Ask a Question 12/8/1611:03 am How Do I Update To Sierra? 2011 iMac with El Capitan —– Robby Comments: One Response to “How Do I Update To Sierra?” Gary Rosenzweig 3 years ago 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. Comments Closed.