Here are some of my operating system re-installation settings. OS X is the only operating system on this page at the moment. Usually with operating systems you just make a clean installation. See also: Operating System Installation Settings.
Comment: you need to have Internet connection for this to work (OS X Mavericks), unless you know how to install OS X from an optical disc, if you have any.
Comment: with my Mac Pro 8-Core, Mac OS X 10.6 Snow Leopard was the first operating system, but OS X 10.9 Mavericks was installed.
Comment: with my MacBook Pro, OS X 10.7 Lion was the first operating system, but OS X 10.11 El Capitan was installed and no installation disk was asked for.
Start your Mac computer.
Restart.
Once the gray screen appears, hold down the Command (⌘) and R keys.
Disk Utility: select startup disk, and the Erase tab.
From the Format pop-up menu, choose Mac OS Extended (Journaled), enter a name for your disk, and then click Erase.
After the disk is erased, choose Disk Utility, Quit Disk Utility.
Select Reinstall OS X, click Continue.
Give your Apple ID credentials when asked (OS X Mavericks).
At the end of the installation you are asked where you are located, keyboard, etc. See more below:
Location: [x] Show all, Finland.
Keyboard: Finnish Extended.
Transfer Information to This Mac: (*) Don't transfer any information now
Sign in with your Apple ID: [Apple ID] [password]
Terms and conditions: Agree
Create a Computer Account: [Full name] [Account name] [Password] [x] Require password to unlock screen
iCloud Keychain: (*) Set up later
Register Your Mac: (*) Register this Mac to my Apple ID
Last modified: November 19th, 2015
Author: Tomi Häsä (tomi.hasa@gmail.com)
URL: http://sites.google.com/site/tomihasa/os-reinstall