Introduction and Video
A small grassy area behind the house will serve as a small patio for the homeowner in this project. A diagonal path divides the yard and limits the size of the patio, so we will orient the rectilinear patio along the path. Our materials are straight-edged and key-shaped interlocking pavers that fit together like puzzle pieces -- a simple pattern that will enable the homeowner to expand the patio in the future. Preparations for the patio include digging a footing and adding a layer of gravel and one of sand as underlayment.

Plan the Patio and Gather Tools
Decide on orientation, dimensions, and materials for the patio and assemble your tools. For the most part, this project requires only yard tools found in the average homeowner's tool shed or garage.

Layout
Mark any obstacles such as an underground electrical conduit that you must avoid as you dig the patio footing. We simply stretch the garden hose across the lawn between the two ends of the conduit visible at the house and the garage. Indicate the perimeter of the patio with wooden stakes driven at the four corners with a mallet. The corner angles should be square so that the shape you mark is actually a rectangle -- this will facilitate laying the pavers. The longer side of our 6 by 8 foot patio will parallel the diagonal path. String a mason's line around the perimeter of the stakes to outline the patio boundaries. Wrap it several times around its stake and temporarily tie it off at the last stake. Mason's line is essentially a heavy-duty braided string that retains its elasticity to stay taut.

Check Your Measurements
Confirm that the marked-off area is a true 6-by-8 foot rectangle. One way to do this is to measure the distance between each pair of diagonally opposing corner stakes with a tape measure. The two distances should be equal. Adjust as necessary until you have a true rectangle.

Remove the Sod and Dirt
Use flat-bladed shovels to cut away the sod about 2 inches outside the mason's line. The extra allowance will enable us to insert retaining strips later to keep the pavers stationary. Rocking the shovel blade forward and backward, and then side to side, will widen the gap and make the boundary more evident in the grass. Pull up the stakes and remove the mason's line once the boundary is well marked. Use the shovels to cut the sod within the patio boundary into small rectangles. Slide the flat shovel beneath the individual squares of sod for easy removal. You can use them to re-sod another part of the yard, if desired. Excavate and remove soil from the rectangle to a depth of 7 inches. Depending on the consistency/hardness of the soil, you can work with shovels, hand diggers, or a full size mattock.

Check the Depth
Measure the depth of the hole at the edges and various points within the rectangle. An easy way to measure is to set a board on edge across the hole and then use a tape measure to measure from the bottom of the board to the bottom of the hole. Our measurement is 7 inches. That allows for 3 inches of gravel, 1 inch of sand and 2 thick pavers.

Add Lining
Line the bottom of the hole with landscape fabric to stop weeds from growing up between the pavers. The fabric is porous to allow rainwater to seep into the ground below.

Add Gravel
Fill the hole with drainage gravel to a depth of 3 inches to provide drainage and stop the water from pooling under the pavers. Distribute the gravel with the back edge of a rake. Use a length of two-by-four lumber as a screed to level the surface of the gravel, dragging it across and back and forth as necessary to even the gravel. The finished patio can only be as level as the gravel and layers beneath. Compact the gravel with a tamper to prevent it from settling unevenly. Measure the depth of the hole again, this time measuring the distance from the surface of the gravel to the bottom of a board spanning the hole. There are 3 inches remaining from the original depth of 7 inches, so we can compute that we have 3 inches left for sand.

Add Sand
Lay two 8-foot lengths of 1 inch diameter electrical conduit on top of the gravel as screed rails for the sand layer that comes next. They will guarantee that the sand is a uniform 1 inch thickness. Pour in the sand and distribute it with the back of a rake. Glide a two-by-four over the sand and conduit as a screed to level this layer.

Begin Laying Pavers
Start laying the pavers between one edge of the patio and the conduit/screed rail. Fit the straight-edged border pieces along the perimeter of the patio. Lay the key-shaped interior stones in an alternating head-to-toe pattern.

Removing the Screed Rails
Work up to the first screed rail, and then remove it. Pour a line of sand carefully in the groove the screed rail left. You only need enough to fill the groove, so be careful not to overfill it. Smooth out the surface of the sand with a wide putty knife.

Edging
Place special L-shaped edging around the perimeter of the patio to hold the pavers in place and stop them from shifting or migrating. The edging fits into the additional 2 inch allowance we left as we were digging the footing. Drive in spikes to hold the edging, placing one at every fourth hole in the ready-made edging.

Final Sanding
Add more sand to the surface of the patio now that the pavers are down. Work the sand into the crevices and tiny gaps between the pavers with a stiff-bristled broom. Adjust your garden hose to a fine spray and clean the surface, washing the sand down into the joints. This final layer of sand will stabilize the pavers to minimize shifting.

Finished
That's it! From an empty yard to a beautiful patio...