There's cleaning off a device because it's bogged down by too many programs, and then there's utterly wiping everything you've done to it. The former is useful if you want to speed things up or you now want a memory-hog download and you're willing to give up some of the programs you previously downloaded. The latter is what you do when it's time to surrender the unit back to your employer, or pass it on to someone else.
To remove programs you've added to the device, select Settings-->System-->Remove Programs. You'll see a list of the programs you've added. They are located in storage memory on your Verizon XV6800. Select the one you want to trash, click Remove. Confirm the action.
But when it's time to really say good-bye, you've got to Clear Storage. Pull down Settings-->System-->Clear Storage. You will see the warning:
"Clear storage will make all of your data lost, and reset all settings to manufacturer default. Do you want to proceed? Please enter the following word "1234" and press Yes button." If you enter the numbers and click yes, your device will crank away for a while, then notify you that it needs to be restarted.
Upon restart, the unit will behave as it did when you first turned it on fresh out of the box, asking you to set the time zone and time, offering you tutorials and guiding you through alignment of the touch screen.