Erase the USB drive. Format it as and name it Untitled . Open Terminal and execute this command:

Apple’s modern app store method can sometimes fail, making a standalone DMG necessary for creating a bootable installer on a USB drive.

Unmount the volume and move the finalized DMG file to your desktop.

As of mid-2026, many users still rely on older Mac hardware for development, media production, or compatibility with legacy software. remains one of the most stable and widely used "older" versions of macOS, offering a perfect balance between legacy support and modern features.

Use the createinstallmedia tool inside the downloaded app to write the files to the image:

Finding a legitimate DMG file can be challenging because Apple prefers distributing updates through the Mac App Store. Avoid third-party torrent sites or unverified download blogs, as these files often contain malware. Method 1: The Official Apple App Store Route (Recommended)