Repairing dead patches in your lawn is recommended to be done in late August or early September.
You can then proceed to patch the area with grass seed or sod.
Remember that your soil level should be 1/2 to 3/4 inch below grade. Cut a piece to the size of the patch and lay it on the soil, then finish trimming it to the correct size. Now press the area with the back of a rake and water thoroughly.
Simply sprinkle it over the prepared area. Be sure to follow the directions on your seed, then water the area sparingly.
Apply a starter fertilizer to the patched area and water again. Keep the patch moist until the area begins to root.