Mark the edge line with a garden hose, string, or spray paint
Remove grass and weeds along the marked line
Cut a clean trench edge with a half-moon edger, spade, or edging tool
Dig down 2 to 4 inches to create a defined border
Remove loose soil and debris from the trench
Shape the bed edge into a smooth curve or straight line
Install edging material if desired, such as stone, brick, metal, or plastic
Backfill and pack soil firmly around the edging
Mulch the flower bed to reduce weed growth and maintain the edge
Trim grass regularly along the border to keep the edge neat
Recut the edge as needed during the growing season