The sharp lines provided by the different materials provide an elevated and unique design. Watch as @kennedyeclark gives ...

Start by moving any mulch out of the way of the edge of the bed. Whether you have rocks, wood or rubber mulch, pull it back from the grass. This makes it easier to run your shovel or edger down.

However, if used in deciduous beds, the combination of fall leaf drop and existing pine straw mulch can be an undesirable mix thus creating more work to address in the fall clean-up process.