you flash it in clockwork, there are some that are built into themes for specific ROMs, some for the stock ROM
I was looking over this and let's clarify for the original poster and anyone else.
This will not increase your speed.
This is for people who use tons of data monthly, and prevents the carrier from lowering your speed after you hit a figure known only to them. If you never hit that figure, you would never see this kick in.
Those who do go over and have been throttled back see a "increase" because they went from the throttled speed back to normal, not anything more than that.
Also, this originally came on for T-mobile, as I looked at the threads, if you use VZ, throttling is done outside the phone as indicated by UMC, so it won't do anything for you.