How to Create an OS X Mavericks Bootable USB and Clean Install on Your Mac
The newest version of OS X Mavericks can be upgraded via the Mac App Store now for free. Over 200 new features have been also released in this new OS X. It provides a boost in performance to your computer and gives better battery efficiency. This is an upgrade version, which means that if you prefer to do a clean install in order to clear all junk files in your system, you have to create a Mavericks bootable USB drive.
Creating a Bootable USB
Download OS X Mavericks from the Mac App Store. Depending on your internet connection speed, it may take awhile as the size of the installer is about 5 GB.
Soon after the download completes, the installation will commence automatically. Exit from here as you will be doing a clean install.
Insert a USB drive of 8 GB or larger to your Mac and launch Disk Utility.
Select the drive and click on the Erase tab, choose the format as Mac OS Extended (Journaled), name it as Mavericks and click on the Erase button.
Exit from Disk Utility and launch Terminal. Then, copy and paste the following command into Terminal and press Enter.
sudo /Applications/Install\ OS \X \Mavericks.app/Contents/Resources/createinstallmedia –volume /Volumes/Mavericks –applicationpath /Applications/Install\ OS\ X\ Mavericks.app –nointeraction
Warning: Rename your USB drive to something else, if your computer is already connected to a drive or partition named Mavericks. Then change the corresponding variable (Volumes/Mavericks) in the above terminal command.
Clean Install OS X Mavericks
Finally, you can restart your Mac with the USB drive is still inserted. While your computer is booting there will be a start up chime, then select your USB drive from the boot menu. Follow the instructions to install Mavericks. The process will take more than an hour and then you will have the newest OS X Mavericks on your Mac.