What are browns and greens? Browns are organic materials that have been dead for a while, or that have been processed, such as dry leaves or shredded paper. They are very stable and break down slowly. Greens are organic materials that were recently alive, such as salad trimmings and yard waste. They tend to decay quickly.
Then, begin to build layers of brown and green materials, in a similar manner to assembling a lasagna. This can be done in one day, or over a period of time as you collect the necessary materials.
Read Lasagna Gardening: A New Layering System for Bountiful Gardens: No Digging, No Tilling, No Weeding, No Kidding! by Patricia Lanza