What you will see are two things.
your cham will become a dull, almost greyish color, like hes been rolling in gravel dust.
and you may see whiteish patches show up. espeically in random places.
My guy started shedding along his spine the first time, then on his ribs the second, then on his tail the 3rd.
Young chams will look fine one minute, then an hour later they will literally look like they exploded out of their skin, and it will be over and done in about 5 hours.
older chams, can take a full day to shed.
adults, oftentimes only shed one body part at a time. first a leg, then a few days later his head, then again his tail.
jsut make sure when your boy does start to shed, that you up the mistinsg and keep the humidity higher to prevent skin from getting stuck. and dont worry if you see him 'yawning' or rubbing on sticks of the cage itself.