I posted about how I migrate an old Mac to a new Mac in a previous post.

After migration, I also wanted to do a clean install on the old Mac, and bring it to factory settings, but with the latest OS X (Mountain Lion for me).

It is very easy.

The steps:

• Restart computer and press Command + R while it restart to get to a menu screen

• Select Disk Utility > Macintosh HD (your startup volume) > Erase

• Go back to menu screen and select Install Mac OS X

Follow through and it will be done!