Cold-Weather Compost Pile:
You need the right Ratio of Carbon to Nitrogen, (C/N).
Adding 1 part Green, to 2 parts Brown, will give the right Mix.

Greens
Fresh Cut Plants add Moisture and Nitrogen.
Chicken Manure has Lots of Nitrogen, Phosphorus, and Potassium.
Don't include Diseased Plants.
Fresh Grass Clippings should be mixed with plenty of dry Browns,
or you'll risk creating a Smelly Pile.
Kitchen Scraps (Carrot Peel etc) should be Buried in the Pile
so they don't attract Animals.
EggShells are OK.

Browns
Brown debris (eg Stalks) add Bulk to the Pile.
Twigs help keep a Pile Fluffy but should be Chipped to Rot Faster.
Leaves are an abundant Carbon source and full of Nutrients.
StockPile them in Fall so that you have them on hand in Summer.
(Hay shouldn't be added to Compost).

Cold Compost
Mix Yard Wastes (eg Grass Clippings, Leaves)
Place them into a Pile and wait 6 to 24 months for the
microOrganisms, Worms and Insects to break down the material.
Add new materials to the top of the Pile.
You can reduce the waiting period by occasionally Turning the Pile
and Monitoring and Adjusting the Moisture Level.

The Compost will be ready when the ingredients are unRecognizable.
Generally, Compost on the Bottom of the Pile finishes First.

Some Like It Hot
You can get HighQuality Compost in under 2 months.
Pile a Critical Mass (1 Cubic Yard) of Greens (1)/Browns(2) Mix,
which is the MINIMUM Volume for a Pile to hold Heat.
Check the Moisture.
Continue adding mixed Greens and Browns until you've built a Pile
that is
3' x 3' x 3' (or 5' Wide at the Base and 3' Wide at the Top).

The microOrganisms' Bodies will release Heat.
The Temperature of the Pile's interior will reach 120 to 150 degrees F.
Turn the pile weekly to regulate Moisture levels.
After about a month, the Hot phase will be done,
and the Pile will finish deComposing at temperatures
between 80 degrees F and 110 degrees F.
The Compost will be ready to use when it No Longer Heats.
Composting 101: Organic Gardening
Gardeners can Speed Composting by creating Optimal Conditions:
Air + Water + Carbon + Nitrogen = Compost Machine
Air: Bacteria need Air.
Turning the Pile helps to improve Air Flow into the Pile.
Water: Microbes need Water.
Too much moisture reduces AirFlow;
too little slows decomposition.
Compost should feel like a WrungOut Sponge.
Carbon: Microbes use Carbon for Energy.
Use Leaves for Carbon.
These ingredients are Browns.
Nitrogen: Microbes need Nitrogen for Proteins.
Nitrogens are generally Green, or Manure.