What is a good way to start a garden bed in my backyard?

Double digging your garden bed can yield great results. Take a shovel and dig one blade length into the soil and set that to the side. Then dig out a second blade length into the soil and set this portion to the side as well. Put the first portion back into the hole you've dug and then place the second portion on the top. By following this method, you can exchange the subsoil and topsoil. Alternatively, you can build a raised garden bed using wood or other material you have hand like corrugated metal. A raised garden bed should have sides that are about 1 - 3 feet high although you can vary this based on your needs. Fill the garden bed with soil mix from your local garden store or from other areas of your yard. Once the garden bed is filled, you can begin planting. Finally, you can use a sheet mulching method to start a garden bed in your backyard. Take thick cardboard or several sheets of a heavy paper material and lay it down on top of a grassy area in your backyard. You want to make sure that the cardboard or paper is overlapped so that it blocks all light to soil and grass underneath it. Once you have finished laying down your material to block the light, spread compost on top so it is three to six inches deep. You can plant into this compost layer. As a final layer, place one to three inches of mulch or straw on top to protect your compost layer.