This is recommended for "clean" installs. You will need a USB drive with at least of space. How to download and install macOS - Apple Support
Also, make sure you have a backup of your important files and data, as installing a new operating system can potentially erase your existing data. download macos sierra 1012 dmg file install
If you need to install macOS Sierra, obtaining a valid or installer file is the first step. Here is a guide on how to get it, install it, and the important caveats you should know. This is recommended for "clean" installs
file. You must "install" this package to place the actual macOS installer into your Applications folder: Apple Support Double-click the InstallOS.dmg file to mount it. Open the mounted disk image and double-click the InstallOS.pkg file inside. Follow the onscreen prompts. This install the OS yet; it merely places an app named Install macOS Sierra Applications Apple Support 3. Install macOS Sierra Depending on your needs, choose one of these two methods: Method A: Direct Upgrade (Easiest) If you need to install macOS Sierra, obtaining
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To download and install macOS Sierra (10.12), you should follow these steps. However, before proceeding, ensure that your Mac is compatible with macOS Sierra. You can check Apple's official website for compatibility details, but generally, macOS Sierra is compatible with:
Before downloading, ensure your hardware is compatible with version 10.12: Late 2009 or newer MacBook Air/Pro: 2010 or newer iMac: Late 2009 or newer Mac mini/Pro: 2010 or newer Memory: Minimum 2GB RAM (4GB recommended) Storage: At least 8.8GB of available space How to Download macOS Sierra 10.12 DMG