You will need to water your new sod within the first thirty minutes after it is installed. You will need to apply around 1 inch of water so that the soil underneath the sod is very wet. You can pull back a corner of the sod to test the soil. Ideally, the soil will be wet for 3-4 inches deep. You can test this by using a sharp gardening tool. Stick the gardening tool down in the soil and see if it pushes in easily for 3-4 inches. If so, you have completed your first step in watering your sod.