Mow the previous lawn as short as possible and kill lawn weeds with an herbicide if they're a problem. If you're changing from another type of grass to fescue and don't want the previous grass to develop as a weed, use herbicide to kill most of it as well.
Till the lawn with a rear-tine tiller set to a depth of 6 inches. Dig out old sod along sidewalks and wherever the tiller can't reach with a spade and toss the clumps into the path of the tiller so they'll be turned under. Go over the lawn once to cut up and bury the old turf, then spread compost and lime or gypsum and go over the lawn again to till them in, advises "Popular Mechanics" magazine in its May 2003 article "Going for the Green."
Rake the surface of the soil smooth.
Broadcast 5 to 6 lbs. of fescue seed per 1,000 square feet by hand or use a seeder. Rake or roll the soil to cover the seed lightly. Spread straw over the soil.
Water the area each day to keep it slightly moist until the seeds germinate, sprinkling it with about 1/8 to 1/4 inches of water. When you can see the new blades of grass, water less frequently but soak the soil deeper.