There is no definitive answer to this as it will depend on the severity of the matting, the cat's personality and your own personal grooming abilities. Assuming that you can manage to groom your cat in some way, try to remove as much of the matting as possible using a brush or gentle coaxing. Try not to pull too hard as this could cause further damage. If the matted fur is very deeply embedded then it may be necessary to see a vet in order to attempt a more advanced grooming method such as shaving or electrolysis.