Alternate the “greens” and “browns” in four to eight inch layers. The exception is grass trimmings. These should be kept to a minimum of two inches as they tend to compact, become slimy and prevent the needed circulation of air. Add water to the browns as they are layered. Ideally the pile should be as moist as a wrung out sponge.
At this moisture level, there is a thin film of water coating every particle in the pile, making it very easy for microbes to live and travel throughout the pile. If the pile is to dry, microbial activity slows down which slows down decomposition. If the pile is to wet it will become heavy and compact, excluding air from the pile, causing odor problems and again slowing decomposition.
The average composter will not usually have enough material to create a compost pile 3 feet deep at start-up. No problem, most single-bin composters build an initial pile and add more materials as they become available. The smaller pile will not attain and maintain the amount of heat needed for fast decomposition but it will decompose at temperatures as low as 50 degrees Fahrenheit, it just takes a little longer.
After about a year, maybe a little longer, check the bottom of the pile for finished compost. The compost is ready for use when the contents have an earthy smell and resembles course-textured, rich brown soil. When it is ready, shovel out the bottom of the pile and add it to your garden or areas of the yard that needs a little fresh dirt. Most simple piles, after the first few years, will produce a few cubic feet of finished compost yearly.