Problem Shedding
All Snakes need to shed their skin as they grow and to rid themselves of dead corneal cells. This is done several times a year and less frequently in older reptiles that have slowed down in growth or reached their average maximum size. Under normal conditions a healthy snake will shed its skin in a single complete shed a little bit like us rolling off a sock. Large pythons however, often shed their skin in a few large pieces and this is quite normal. Sometimes however a snake can have difficulty in shedding its skin. The most common cause of problems in shedding is because of the lack of humidity that they are exposed to in the latter stages of the shedding cycle. This seems to happen far more often during winter months because the air in winter tends to be a lot drier. This lack of humidity can be easily corrected or increased by offering a water dish that has a large surface area to aid evaporation. You can also increase it even further by placing the water dish closer to the provided heat source. If you are faced with a snake that has not shed its skin properly it will usually require manual assistance to remove it.
When this condition happens the skin will appear very dry and crinkly (figure 1). Sometimes the old layer will be stuck so well against the new skin underneath that it is very hard to peel off. Often you can remove the skin by just running or rubbing your fingers, hand or a damp cloth over the snake's body starting from its head area and working back the skin towards the tail area. Snakes scales are a bit like over lapping roof tiles and it is far easier to work from the head back towards the tail section.
If this proves unsuccessful, then the snake will then have to be placed in a container of water to soak for a few hours, and sometimes up to 48 hours depending on how stubborn the skin is (figure 2). It is important that the water temperature in the container doesn't get too hot or cold as the snake cannot regulate its body temperature when in constant contact with water. I tend to use a 9 litre plastic container sitting under a heat cord connected through a thermostat. It can also be of use, to place within the soaking container a small rock or something similar that will provide an abrasive rubbing surface. This will often assist the removal of the skin should the snake continue to try and shed it off itself whilst in the water. If you choose to add a rock you must make sure that it does not protrude too much above the water level as this can offer an area for the snake to escape the water.
After the old layer of skin has become softened enough you should have no difficulties in peeling the skin off. The use of rubber washing gloves can be useful when performing this procedure as they provide excellent grip. Sometimes the manual assistance is not required as the snake will manage to shed itself while in the water (figure 3).
Another method that I have read about before is to place the snake into a wet cloth bag. You have to be very careful with this method though as a wet cloth bag can make it  extremely difficult for the reptile to breathe through the material. I have seen snakes die before when cloth transportation bags have become wet. On rare occasions you may find that a snake has failed to shed the eye scale, or scales. To remove these scales you can wrap a small piece of sticky tape around your finger or use a cotton bud. You should then gently press against the surface of the scale and carefully roll and peel the scale away. Alternatively you can use a pair of tweezers and very carefully pry up the edge of the stuck scale and slowly roll it off. If there is any difficulty or resistance with either method then do not continue as you might damage the eye. I have personally seen two disasters from keepers who failed to do this procedure carefully and the result was the entire lens had completely pulled off the eye. One was a green tree python Morelia viridis which later ended up dying, and the other was a Black-headed python Aspidites melanocephalus, and although the wound eventually healed, it was blind and disfigured. It is debatable whether or not it is absolutely necessary to remove all problem eye scales and some people prefer to leave it there and see if it will come off in the following shed. There have been stories of eye infections as a result and failure to remove these scales. I have however, come across snakes in the wild that have had retained eye scales and I have witnessed it being discarded on the following shed. I once came across a Pilbara Woma who had an eye that appeared to be grossly enlarged. Upon closer examination it seemed that there was fluid behind the eye scale which was forcing out the circumference of it. Although the fluid seemed transparent it appeared that the snake was blind in that eye and to me it looked like it had been like that for years. I took it for granted that this was some sort of birth defect only to be pleasantly surprised when he shed his skin two months later and had a perfectly normal looking eye.