Gather all your materials. You will need a hand tamp, a shovel, cinder blocks, measuring tape, gravel, dry mortar, water, a trowel, a leveler, a carpenter's square, metal braces, a grill top and plenty of bricks.
Pick a spot for your barbecue pit. The pit itself needs to be about 15 feet square (3 feet by 5 feet). That's about 4.6 meters square (0.9 meters by 1.5 meters). The area should be kept clear of brush and any other fire hazards.
Mark the area where you plan to build, and dig a pit 8 inches (20 centimeters) deep. Level off the bottom of the pit with a hand tamp. Before you go any further, soak your bricks with water so they don't act like a sponge under wet mortar.
Spread a 2-inch (5-centimeter) layer of gravel in the trench you just dug. Level that off with the hand tamp, too.
Mix the dry mortar with water. For the rest of your project, add more water as needed to keep the mortar moist. Spread a 2-inch (5-centimeter) layer on top of the gravel, and level it off with a trowel. Work quickly so your mortar doesn't harden before your space is level.
Place the cinder blocks on the edges of the mortar, leaving a small hole or two to drain water. Use the leveler to make sure the cinder blocks are even, and use the carpenter's square to check all of your corners.
Spread mortar on top of your cinder blocks, and place bricks side by side over them. The double layer of bricks strengthens the structure. Remove any extra mortar as you go -- it'll be hard to remove once it's dry.
You can also apply mortar to the bricks individually. Using the trowel, put mortar on the sides and bottom of the brick, wiping away the excess after you add the brick to your structure.
Continue applying mortar and adding bricks until you reach the desired height for your barbecue pit. Check the level and corners frequently.
Place metal braces in the last layer of mortar while it's still wet. The braces will hold the grill top, so they should face inward. The next day, make sure the mortar has set, and place the grill top on the metal brackets. To learn more about BBQ & Grilling check out the BBQ & Grilling channel.