Design a detailed plan or diagram on graph paper demarcating the placement of a sandbox, swings, slides and other play equipment, along with any grassy section for rough play. Incorporate equipment your child loves and will use. Decide whether you want to transform the entire backyard into a playground, or a particular portion of it. Make sure you include edging that contains sand or cordons off different sections of the playground.
Frame the playground with edging material. Dig a trench around the demarcated area and install the plastic edging. Back fill with dirt so it holds the edging material in place. The edging gives the playground a manicured look and prevents grass or weeds from growing inside.
Place the swing sets and play equipment in their designated places. Refer to the graph paper for appropriate positions. Install soft landing spots to protect the children from injury. Depending on personal taste, dig a 1-foot-deep square or rectangular trench under swings, slides, trampolines or monkey bars and fill with sand, or spread outdoor rubber mats under the equipment.
Install a sandbox over the selected spot. Assemble it yourself by hammering lengths of wood to create a square or rectangular frame and spread weed netting in its base before filling it with sand. Keep it at least a foot deep and add pails, shovels and toys. You can also purchase one to fit your needs from a toy or retail store. Keep it under a covered spot to prevent rain or debris from ruining it, or select one with a lid if you choose to buy one.