Measure how wide and deep you want the grill base to be. If you plan on using 4-by-8-inch red bricks as a simple and economical surface, an easy measurement is 67 inches square. This forms a square where all the bricks fit evenly and you are not required to cut any bricks to fit. Mark the area with four stakes and string, measuring twice to make sure your diagonal measurements are the same from corner to corner.
Remove the soil from the measured area to a depth of 6 inches with a shovel, placing the soil in a wheelbarrow for easy transport. Check the base with a level to make sure it is even so your grill won't lean.This type of installation is more stable than laying bricks on the surface of the ground.
Cut four sections of 2-by-6 exterior-grade lumber into 65½-inch lengths. Place them in the hole and screw them together at the corners with 2-inch galvanized screws. These will form the frame of your base.
Pour 3 inches of gravel into the hole and level it out with a garden rake. Tamp it down with a pole tamper to make sure you have a firm and level surface.
Cover the gravel with a section of landscape cloth. This will prevent the sand from washing out after a few storms. Allow the cloth to cover the bottom of the hole, as well as the sides, allowing it to overlap the top edges by 6 inches.
Pour 1 inch of sand over the landscape cloth and level it with a straight section of wood.
Lay out the brick horizontally in any pattern you like. Place the bricks tight against each other and against the framing. Using the measurements listed, you need 128 bricks to fill in the base. Tamp the bricks in place with a rubber mallet so that they sit flush with the wood border.
Trim the excess landscape cloth from around the edge of the base, cutting it even with the wood frame.
Pour sand over the top of the bricks and use a broom to push and pull it into the cracks between the bricks and between the bricks and the wood frame. Continue to add sand until the surface is level.