set the metallic texture picture to "overlay", and the water drop picture to "normal." the water drop picture must be UNDER the metallic picture.
step 8 of 9
now, very important step. to make the picture look like the carbon fiber was under the water, you must distort a little the METALIC PICTURE (especialy where there are "holes") with the smudge tool.
step 9 of 9
to finish, just darken a bit the corners and duplicate the different layers with "overlay" option on.