Please Backup your Data Before you start Installing Mavericks.
Once you’ve downloaded Mavericks, find the installer on your Mac. It’s called Install OS X Mavericks.app and it should have been downloaded to your main Applications folder (/Applications).
Right-click (or Control+click) the installer, and choose Show Package Contents from the resulting contextual menu.
In the folder that appears, open Contents, then open Shared Support; you’ll see a disk image file called InstallESD.dmg.
Double-click InstallESD.dmg in the Finder to mount its volume. That volume will appear in the Finder as OS X Install ESD.
The file you want to get to is actually another disk image inside OS X Install ESD called BaseSystem.dmg. Unfortunately, BaseSystem.dmg is invisible, and because this is a read-only volume, you can’t make BaseSystem.dmg visible. Instead, you’ll mount it using Terminal, which makes it visible in Disk Utility. Open the Terminal app (in /Application/Utilities), and then type open /Volumes/OS\ X\ Install\ ESD/BaseSystem.dmg and press Return.
Launch Disk Utility (in /Applications/Utilities). You'll see both InstallESD.dmg (with its mounted volume, OS X Install ESD, below it) and BaseSystem.dmg (with its mounted volume, OS X Base System, below it) in the volumes list on the left.
Select BaseSystem.dmg (not OS X Base System) in Disk Utility’s sidebar, and then click the Restore button in the main part of the window.
Drag the BaseSystem.dmg icon into the Source field on the right (if it isn’t already there).
Connect to your Mac the properly formatted hard drive or flash drive you want to use for your bootable Mavericks installer.
In Disk Utility, find this destination drive in the left sidebar. You may see a couple partitions under the drive: one named EFI and another with the actual drive name. Drag the latter—the one with the drive name—into the Destination field on the right. (If the destination drive has additional partitions, just drag the partition you want to use as your bootable installer volume.)
Warning: This step will erase the destination drive or partition, so make sure it doesn’t contain any valuable data. Click Restore, and then click Erase in the dialog box that appears; if prompted, enter an admin-level username and password.
Wait for the restore procedure to finish, which should take just a few minutes.
In Disk Utility, select BaseSystem.dmg on the left (not OS X Base System) and click the Eject button in the toolbar. This action unmounts the disk image named OS X Base System. (If you don’t do this, you have two mounted volumes named OS X Base System—the mounted disk image and your destination drive—which makes the next step more confusing.)
Open the destination drive—the one you’re using for your bootable install drive, which has been renamed OS X Base System. Inside that drive, open the System folder, and then open the Installation folder. You’ll see an alias called Packages. Delete that alias.
Open the mounted OS X Install ESD volume, and you’ll see only a folder called Packages. Drag that folder into the Installation folder on your destination drive. (You're basically replacing the deleted Packages alias with this Packages folder.) The folder is about 4.8GB in size, so the copy will take a bit of time, especially if you’re copying to a slow thumb drive.
Eject the OS X Install ESD volume.
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) in Mac OS X, then select the AirPort Extreme Base Station (802.11n) to which the USB hard drive is connected.