How to Create a Bootable macOS USB Installer
🔹 Step 1: Prepare a USB Drive
• 🧰 Requirements: USB drive with at least 16GB of storage.
• 💾 Backup: Save any important data—it will be erased.
• 🪄 Format using Disk Utility:
• Open Disk Utility (Finder → Applications → Utilities → Disk Utility).
• Select your USB drive in the sidebar.
• Click Erase.
• Choose Mac OS Extended (Journaled) as the format.
• Use GUID Partition Map for Scheme.
• Name it something simple like MyUSB.
💡 Hint: The drive name will be used later in Terminal, so avoid spaces or special characters.
🔹 Step 2: Download the macOS Installer
• 🍎 Open the Mac App Store.
• 🔍 Search for the macOS version you want (e.g., macOS Ventura, macOS Monterey).
• ⬇️ Click Get or Download.
• 📂 The installer will appear in your Applications folder once downloaded.
💡 Hint: If you can’t find an older version, Apple provides direct links on its support site.
🔹 Step 3: Open Terminal
• 🖥️ Open Terminal (Finder → Applications → Utilities → Terminal).
• ✍️ You will type a command that creates the bootable installer.
🔹 Step 4: Run the createinstallmedia Command
• 🖱️ Use this command template (replace MyUSB with your USB drive name and adjust macOS version if needed):
• sudo /Applications/Install\ macOS\ [Version].app/Contents/Resources/createinstallmedia --volume /Volumes/MyUSB
• 🔹 Example for macOS Ventura:
• sudo /Applications/Install\ macOS\ Ventura.app/Contents/Resources/createinstallmedia --volume /Volumes/MyUSB
• ⌨️ Press Enter.
• 🔑 Enter your administrator password when prompted.
• ⚠️ Hint: Terminal will warn that the drive will be erased—type Y to confirm.
🔹 Step 5: Wait for the Process to Complete
• ⏳ Terminal will show progress as it copies the installer to the USB drive.
• 🕒 This may take 15–30 minutes depending on USB speed.
• ✅ Once done, Terminal will display “Done”.
💡 Hint: Do not eject the USB until Terminal confirms completion.
🔹 Step 6: Boot from the USB Installer
• 🔄 Restart your Mac.
• ⌥ Hold Option (⌥) key immediately after the startup chime.
• 💽 Select the USB drive (usually named as the macOS version).
• 🖥️ The Mac will boot into the macOS Recovery / Installer screen.
💡 Hint: From here, you can install macOS, erase a disk, or restore from backup.
✅ Pro Tip: Keep the USB installer safe—it can be reused for clean installs or troubleshooting any Mac.