I am at work til 7:30 today... but essentially you just unscrew the faucet head that you are plugging the rodi unit into, and then bring the rodi unit in... and get a converter that will screw into the same fitting faucet head, and your rodi unit. I don't know which unit you have... but mine was the size of a garden hose. So I just bought an adapter that screwed into my current sink and sized it with a garden hose fitting. The sizes are all at home depot, it's just a matter of trying a few out to fit them.
If you have any trouble, I am sure someone at home depot would be willing to help. And if not, I can try to find the part number when I get home... but your faucet head might be different than mine.