Update macOS 10.15: Catalina
1 First of all, open the App Store and find the Mojave operating system. Do a search if it’s not immediately visible on the front page. Click on macOS Mojave to get to the download page. 2 When you get to the Catalina download page, you can read all about the new OS. When you’re ready, click on Download. It may take some time if you have a slow Internet connection. 3 When the installer is fully downloaded, it automatically launches with this screen. Click Continue if you’re ready to install and if not, quit it and install from the Applications folder later. 4 Next step is terms and conditions. You have to click on Agree to continue. If you don’t have time to read them, there’s a copy available in About This…