Measuring the diameter of the space where you intend to to build the firepit and the length of an individual brick to calculate the number of bricks you will need.
Multiply the diameter measurement by ? (approximately 3.14) to calculate the circumference of the space. Divide the product of these two figures by the length of an individual brick to determine the exact number of bricks you will need.
Use a piece of chalk to draw a circle on the ground where you want to build the firepit.
Place one layer of bricks around the chalk circle end-to-end. Continue to add layers on top of the first layer one by one until the firepit reaches the desired height. Each brick in a new layer should overlap two bricks in the layer directly beneath it.