A compost bin is an ideal addition to a household or garden in order to provide your own food for your plants and organically get rid of a lot of your waste. There are four basic ingredients that need to be used in equal parts for composting: nitrogen, carbon, water and air. There are literally hundreds of items that qualify for being the nitrogen or carbon elements of composting. After layering these items, all it takes is time in order for the organisms to break down and provide compost.
Nitrogen materials include most green materials. These include things such as grass clippings, landscape trimmings, vegetable and fruit trimmings or peels, freezer-burned vegetables or fruit, rinds, houseplant trimmings, spices, pine needles, leaves, seaweed, kelp, hops, manure, eggshells, etc. Bury food scraps deep to avoid pests or odors.
Carbon material pertains to brown (dry) yard and garden material such as dry leaves, twigs or hay. Chop, break up or shred large pieces to 12 inches or shorter for quicker composting. Other items include untreated wood chips and sawdust, paper napkins, burlap coffee, wood ashes, coffee or tea grounds, matches, hair, paper shreds, etc.
Water is a very important element to a compost bin. If the bin is too dry, it will not compost. To test for adequate moisture, reach into your compost pile and grab a handful of material and squeeze it; if a few drops of water come out, it's probably got enough moisture; if it doesn't, add water. When you add water, let it run down the sides so it reaches all parts of the compost bin.
Air is necessary for composting to happen, so that the bacteria and fungus that are in your compost pile can live and work. There needs to be enough air circulation, so you should fluff up your compost pile regularly. Layer compost bin ingredients, and use a shovel or trowel to sift through the compost bin to get fresh air to the ingredients weekly.