A clean install of macOS erases your drive and installs a fresh system, ideal for fixing issues or preparing to sell your Mac. 1. Back up your data using Time Machine or manual copy, noting app licenses. 2. Boot into Recovery Mode—Apple Silicon Macs hold the power button; Intel Macs use Command Option R. 3. In Recovery, use Disk Utility to erase your startup disk: select the drive, set name to Macintosh HD, format to APFS, then click Erase. 4. Reinstall macOS from Recovery, selecting the erased drive as the destination, requiring a stable internet connection. 5. Set up your Mac as new, choosing not to transfer data and creating a fresh user account. 6. Restore only essential files manually and reinstall apps from trusted sources to avoid carrying over old issues. This process ensures a clean, optimized system with improved performance, completed safely after verifying backups.

A clean install of macOS erases your drive and gives you a fresh start—great for fixing issues, boosting performance, or preparing to sell your Mac. Here’s how to do it step by step.

Back Up Your Data First

Before wiping anything, make sure your files are safe.

• Use Time Machine to back up to an external drive.
• Alternatively, manually copy important files to an external drive or cloud storage.
• Note down app licenses or activation keys if needed (e.g., creative software).

?? A clean install deletes everything. Double-check your backup.

Boot Into Recovery Mode

This lets you reinstall macOS without loading the current system.

1. Shut down your Mac.
2. Turn it on and immediately hold one of these key combinations:
   • Apple Silicon (M1/M2/M3 Macs): Hold the power button until you see startup options.
   • Intel Macs: Hold Command (?) Option (?) R until the Apple logo or globe appears.
3. Wait for the macOS Recovery screen.

Erase Your Startup Disk

This clears all data for the clean install.

1. In Recovery, open Disk Utility.
2. In the sidebar, select your internal drive (usually named “Macintosh HD”).
3. Click Erase.
   • Name: Macintosh HD (or your preferred name)
   • Format: APFS (recommended for most Macs)
   • Scheme: Not always visible—APFS uses a default scheme.
4. Click Erase, then Done.
5. Close Disk Utility.

Reinstall macOS

Now install a fresh copy.

1. Back in Recovery, choose Reinstall macOS.
2. Click Continue and follow prompts.
3. When asked, select the erased drive (e.g., “Macintosh HD”) as the install destination.
4. Wait—this can take 20 minutes to over an hour, depending on internet speed.

? You need a stable internet connection. The installer downloads the latest compatible macOS version.

Set Up Your Mac Like New

After installation:

• Go through the setup assistant.
• Choose your language, region, and network.
• At the “Transfer Information” screen, pick Don’t transfer any data to keep it clean.
• Create a new user account.
• Finish setup and sign in to your Apple ID.

Restore Only What You Need

Instead of full restore, consider:

• Manually copying back documents, photos, etc., from backup.
• Reinstalling apps fresh from the App Store or official websites.
• Avoid transferring system settings or caches—they can bring back old issues.

That’s it. You now have a clean, fast macOS install with no clutter. It’s a simple process but powerful for keeping your Mac running smoothly. Just remember: backup first, then wipe.

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