Quick Answer: How to Clean Install Os X?

Booting From the OS X El Capitan Installer

• Insert the USB flash drive containing the OS X El Capitan installer into your Mac.
• Restart your Mac while holding down the option key.
• After a short delay, your Mac will display the OS X Startup Manager, which will display all of your bootable devices.

Booting From the OS X El Capitan Installer

• Insert the USB flash drive containing the OS X El Capitan installer into your Mac.
• Restart your Mac while holding down the option key.
• After a short delay, your Mac will display the OS X Startup Manager, which will display all of your bootable devices.

Step 3: Clean Install macOS Sierra on your startup disk

• To format a USB drive launch Disk Utility (Finder -> /Applications/Utilities/Disk Utility).
• Select your USB drive under External.
• Click the Erase tab at the top of the Disk Utility window.

How to Perform a Clean Install of OS X Mavericks

• Restart your Mac while holding down the option key.
• Select Mac OS Install ESD as your boot volume.
• After you’ve booted into the installer, you’ll be able to erase your Mac’s main hard drive using Disk Utility, or choose a separate hard drive or partition to install OS X.

How do I do a clean install of OSX?

To erase your Mac’s main drive:

1. Go to System Preferences.
2. Сlick Startup disk and choose the installer you just created.
3. Restart your Mac and hold down Command-R to boot into recovery mode.
4. Take your bootable USB and connect it to your Mac.

How do I wipe my Mac and reinstall?

Select your startup drive on the left (typically Macintosh HD), switch to the Erase tab and choose Mac OS Extended (Journaled) from the Format drop-down menu. Select Erase and then confirm your choice. Quit out of the Disk Utility app, and this time choose Reinstall OS X and Continue.