Place two wood stakes in the ground beside the exterior wall of your house. Hammer them into the ground with a rubber mallet.
Hammer two more stakes about 10 feet away from the house, parallel to the stakes near the house.
Wrap string around each stake, just 5 to 6 inches from the ground, creating two lines running perpendicular to the house.
Hang a line level on each string and adjust the two strings as necessary until the strings wrapped around the stakes away from the house are 2 to 3 inches lower to the ground than those next to the house, creating a visible downward slope away from the house.
Spread dirt/soil inside the strings on your side yard to match the slope in the strings, using a landscaping rake.
Smooth the dirt/soil using a 2-by-4 board like a screed, smoothing from the exterior of the house away from the home to finish.