Upon completion of the USB formatting, locate Install Mac OS X Mavericks.app (downloaded in step #1 to the Applications folder, by default).Launch the Terminal.app by selecting it from the /Applications | Utilities folder and execute the following command ( Figure C)*:.Click on the Options button, select the radio button for GUID Partition Table, and click OK ( Figure B).Select Mac OS Extended (Journaled) for the format-type from the drop-down menu ( Figure A).Click the drop-down menu, selecting 1 partition.Click on the USB drive from the left-hand menu and select the Partition tab.Insert the USB drive into the Mac and launch Disk Utility.
Using a Mac with at least OS X 10.6.8 installed, access the Mac App Store and download the Mavericks (10.9) app installer.
In April, I wrote an article on TechRepublic about how to create a bootable USB to install OS X. Jesus Vigo goes over the steps to create a bootable USB to install OS X 10.9 (aka Mavericks). How to create a bootable USB to install OS X Mavericks