It’s still not too late to prepare your yard for winter. There are some priority tasks that will protect all of the work you did this summer.
This Old House suggests the crucial steps for your lawn are aerating the turf to allow fertilizer and water to reach the roots, then reinvigorating any worn patches with seed and compost. Always make two passes when you fertilize, aerate, and seed, using crisscrossing paths to avoid striped patterns in the spring.
Repair your lawn with perennial rye-grass, which has fast germination. Top-dress with 1/4 inch of compost or soil, keeping everything moist but not soggy to thwart mold growth. Try saving pruning until the spring; it promotes growth, which you want to avoid before winter.
Cover your vegetable garden with a nitrogen-rich clover that you can turn over in the spring, or with burlap over the beds. Transplant and mulch before the first frost, and clean the perennials out of your flowerbeds.