We built this 3 bay pallet compost pallet bin a year ago. We used the far right bin to compost in for a year. The middle bin is for storing higher carbon organic matter til needed (straw, leaves, weeds). The far right bin now has a year's worth of compost in it, and we will leave it to age while we add to the far left bin.
Our 3 bay compost bin system
Lid only added when heavy rains are raining. Compost needs a lot of water, so normally keep it uncovered.
Burlap keeps the contents of each bin in but allows airflow
A "sponge" of airy organic matter at the bottom of the compost prevents any leaching
Middle bin is "browns" storage: leaves, leaf mulch, straw or weeds to add to the piles