Identify the cause of the patchiness
Rake out dead grass and debris
Test the soil pH
Aerate compacted soil
Loosen the topsoil
Add compost or topsoil if needed
Overseed the bare patches
Match the seed to your grass type and climate
Keep the seed evenly moist
Apply a light layer of straw or mulch
Avoid heavy foot traffic on repaired areas
Fertilize lightly after new grass starts growing
Mow at the proper height
Water deeply and less often once established
Control weeds, pests, and disease
Refill low spots that collect water
Improve drainage if needed
Repeat overseeding in thin areas as needed