The answer to 'how to install mulch' is to spread a 2-4 inch layer of mulch over the soil around plants and trees. Mulch helps retain moisture, suppress weeds, and insulate plant roots. Start by clearing any existing weeds or debris from the area. Then apply the mulch in an even layer, being careful not to pile it directly against plant stems or tree trunks. Mulch should extend several inches beyond the plant's drip line to provide the most benefit.
Reapply mulch annually in the spring or fall to maintain the desired depth. Avoid using too much mulch, as it can prevent water and air from reaching the soil. If you have a large area to cover, consider hiring a professional landscaper to ensure the job is done properly.