Mow the grass short
Mark low spots and high spots
Remove rocks, sticks, and debris
Fill small low spots with a topsoil-sand mix
Use a rake to spread the fill evenly
Water lightly to help the soil settle
Add more mix if the area sinks
For larger low areas, cut and lift the sod
Add soil underneath to raise the area
Re-lay the sod and press it down
For high spots, cut into the turf and remove excess soil
Re-set the sod and tamp it flat
Use a lawn roller lightly if needed
Check the level again after settling
Repeat filling and smoothing until even
Overseed bare areas if needed
Water the lawn regularly after leveling