Spread the new seed over the soil, then rake it in to a depth of about 1/4 inch.
Cut open the hay bale with a utility knife if the bindings are twine; use wire cutters if the binding is wire.
Take handfuls of hay from the bale, then shake it out over the seeded ground. Don't pack it down. Sprinkle the hay until it is 2 to 4 inches deep.
Spray water over the top of the hay every day or so to keep the soil moist.