Take a walk around the edge of your garden, and with each step you trim the edge of your lawn.
Easily attachable to your boots/gardening shoes, every time you step down closes the clipper and cuts the grass. When you lift your feet, a spring under your boots opens clipper while the other foot does the clipping.
That is why I call it EDGEREASE. No bending, no stooping, no gasoline engine needed, just stroll around the edge of your lawn for that neat, well trimmed look.