1. Prepare the area ( edge , pull weeds out, clean bed ) 2. Lay down anything you want under the mulch, such as landscaping weed control fabric or plastic. 3. Add a generous thickness of mulch. The depth of mulch is really important if you want to retain moisture and prevent weed growth. Aim for at least two to four inches of depth ( optional ) 4. Pull back the mulch from the edge and spread the mulch with a rake as needed for an even layer.