Remove any leaves as they fall. Mow the grass until temperatures dictate otherwise. Over sow or re-turf the lawn if necessary if bare patches have appeared due to heavy use.
JANUARY TO MARCH
Not a lot to do to the lawn during this period, the grass growth is slowed right down because of the cold conditions. Try to stay off the lawn if it is covered in frost or very wet. Perhaps get the lawn mower serviced ready for spring.