1. Apply winterizing fertilizer: Fertilizing in the fall gives your lawn the nutrients necessary to build a deeper root system. Fertilizers high in potassium are best for fall because it stimulates root growth.
2. Rake/dethatch: Rake the sod using a heavy rake to dethatch the lawn. After the last of the tree leaves have fallen, rake the lawn and remove all of the leaves and debris.
3. Patch bare spots: If your sod has bare spots re-sod the areas. To do this, remove any damaged sod, using a knife, cut the new sod to fit the area, spread a bit of fertilizer and lay the new sod on top. Tamp the sod down to make sure the root system has good contact with the soil. Water the new sod regularly for several weeks until it is established.