Well, like HybridCreations mentioned, you should read the manual, as it's quite an extensive subject.
But as a small tip: if you look at the DVX front on; i.e. looking straight at the LENS - there's a small button on the bottom right; that's AWB.
But you NEED to read all about it also, there's a lot more to know...
Yes, I suppose I jumped on the RTFM tip a tad early. That AWB button is used to take a white balance (and toggle between 3200 and 5600 presets, AND take a black balance) I thought he was referring to Auto Tracing Whitebalance which is in the menu. Read up.
-Ryan