Attach your string to a weight scale (or a hook of some kind) at the same place you attach your release and pull down just like you are checking the weight. Make sure that the modules are on top so you can see them.

Look at the flats (draw stops) on the modules and see if the modules are hitting both cables at the same time at full draw. If they are not then twist the cable of the cam that is "faster" or fully rotated. By twisting it you are shortening it and this will bring it around to being in synch with the other cam.

After you get them in synch with each other you can twist both cables equally and get the cams back into their optimim rotation between the hash marks.