I just finished creating a Mavericks boot disk from the directions given on the MacWorld Web Site - LINK.

I want to point out that this procedure should not be attempted by anyone who is not familiar with using Disk Utility or a new Mac user. MacWorld lists an alternate method of creating the boot disk by using a utility called "Lion Disk Maker 2.app" which you can download from here. This will automate the process. Even though it's called Lion Disk Maker, it's been updated to work for Mavericks.

In either method you will need an 8 GB flash drive or SD card. You can also use an external hard drive. The procedure has to be accomplished before installing Mavericks or the files that are needed to make the boot disk will be deleted during the Mavericks installation.

Backup everything first!