How to Clean Up a Mac Computer

For OS X 10.7 and above

Data backup . Cleaning your Mac erases everything, including the operating system. Therefore, it is best to save a backup copy on an external hard drive or DVD.

Open the Apple menu. This black apple icon is in the upper left corner of the screen.

Click Restart… (Restart). This button is near the bottom of the menu.

Click Restart to confirm. The Mac will be turned off and restarted immediately.

Wait for your Mac to turn off completely.

⌘Press and hold the +R keys while your Mac is restarting.

Release the keys when you see the Apple logo. The "macOS Utilities" window will be displayed.

Click Disk Utility . This button is at the bottom of the list.

Click Continue . This button is located in the lower right corner of the window.

Click your Mac's hard drive. This drive is in the upper left corner of the window, just below the internal drive.

Click Erase . This button is near the top center of the window.

Name the drive. Type a name in the "Name:" field.

Click "Format:". This is the step to open the drop-down menu.

Select format. To reinstall the MacOS operating system, you can choose from the following options:

Mac OS Extended (Journaled) to clean up quickly.

Mac OS Extended (Journaled, Encrypted) to clean in a more secure way.

Click Erase . This button is located in the lower right corner of the window. The cleaning process will begin.

How long it takes to clean up the drive depends on the drive capacity, the data stored, and whether you choose Encrypted format or not.

For OS X 10.6 and below

Data backup . Because cleaning your Mac will erase everything (erasing the operating system), you need to back up a copy on an external hard drive or DVD just in case.

Insert the installation disc into the device. Insert the included DVD or CD into your computer's drive and wait for the disc to be recognized.

If you're using a USB drive and not an installation disc, you'll need to insert the USB drive.

Open the Apple menu. This menu has a black apple in the upper left corner of the screen.

Click Restart… . This button is near the bottom of the menu.

Click Restart to confirm. This step instantly shuts down and restarts your Mac.

Wait for your Mac to turn off.

Press and hold Cas your Mac restarts.

If you're using a USB drive instead of the installation disc, you'll need to keep the ⌥ Option.

Open Disk Utility . This button is in the "Utilities" section of the Installation menu.

Click your Mac's hard drive. This drive is located in the upper left corner of the window, below the internal drive.

Click Erase . This button is at the top of the page.

Name your drive. Enter a name in the "Name:" field.

Click "Format:". This step opens the drop-down menu.

Select format. If you intend to reinstall the OS X operating system, select Mac OS X Extended (Journaled) .

Click Erase . This button is located in the lower right corner of the window. The cleaning process will begin.

The amount of time it takes to free up a drive will vary depending on the size and amount of data stored on your hard drive.