When you start a new garden or need a fresh start in your current garden, the easiest way to clear the growth is to smother it. This works especially well as preparation for spring planting when you are finished gardening in the fall.
Trim tall weeds with a weed-clearing tool or any appropriate gardening tool. Any plants that are too thick can be stomped down.
Leave the clippings where they fall. They are a great source of nitrogen for your soil.
Lay down the newspaper or cardboard where you want to be weed-free.
Water the newspaper or cardboard with the hose. Be sure that the cardboard is completely saturated. The weeds will be cut off from the air and sun they need to survive. The nitrogen from the living plant matter combined with the carbon of the newspaper or cardboard will act as compost for the soil.
Keep the newspaper or cardboard damp by watering it every or every other day. In addition, try to occasionally walk or stomp over the newspaper or cardboard to help thwart any aggressive weeds and to ensure that all plant matter is close to the ground for decomposition.
Wait at least two weeks for plant matter to begin to break down before you cut through the newspaper or cardboard to plant any new plants in the space. As time passes and the plants begin to decompose, earthworms will be attracted to the moist soil just beneath the cardboard. The worms will tunnel through and aerate the soil.