Answer:
Smaller ears, more dense and light coloured fur.
Step-by-step explanation:
Smaller ears means that the surface area of the animal is decreased.
Less surface area = Less heat loss
Denser fur is self-explanatory. If the animal has more fur, that means that it will have better insulation. The light colouration of the fur is mainly for camouflage but it can also serve as a way of insulating/preventing heat from escaping.