Lay out the path of the edging, marking the outside corners with wooden stakes pounded into the ground with a mallet. Remember that the bricks take up space. Mark your corners about 4 inches outside the garden or area you are edging. In laying brick edging, you follow the contours of the ground instead of trying to make the edging plumb level.
Wind string around one of the stakes and run it to the next stake, winding it around that stake and continuing until you have defined the entire border. If it is important to you to have corners at a 90-degree angle, check the corners with a carpenter's square and adjust as necessary.
Measure the entire length of the edging using a measuring tape, reading the length in inches. Calculate, based on the length of the brick you have selected, how many bricks you will need. Divide the total edging measurement (in inches) by the measurement of the length of one brick (in inches).
Mark the string border by spraying the line with landscaper's spray paint. Remove the string but keep the wooden stakes in place.
Dig a trench 6 inches deep and 1 inch wider than the width of your bricks using a square-bladed garden spade. Make sure the outside edge of the trench is absolutely vertical.
Line the bottom and sides of the trench with landscaping fabric. Fill the trench with 2 inches of 3/4-inch crushed limestone. Use the 2 x 6 to tamp and level the crushed limestone. Add a 1-inch layer of mason's sand and tamp and level it with the 2 x 6.
Reinstall the string between the wood stakes to define the border again. Use a sting level to place the string 2 inches above grade. This marks the top of the bricks that form the edging.
Set the bricks into the trench. The bricks should be placed on a side, not flat. Tightly butt the bricks end to end, using the 2 x 6 to jam them up against the outside vertical wall of the trench. Check to make sure the tops of the bricks are even with the string as you go along. Adjust as necessary, adding or taking away sand from under the bricks. Continue until all of the edging is laid.
Back fill the trench on the backside of the bricks with garden soil, tamping it down with the 2 x 6. Add sand to fill any spaces between the bricks.