Our garden is pretty small. I take four old skids, stand them on end and make a box. I use 4" screws and just screw the tops together, one screw in each corner.
I start filling the first box with scraps, alternating green and brown material, with some occasional chips, etc... pretty much anything that was once plant matter. Coffee grounds and egg shells, too.
After a few weeks of this, the box gets full. Then I take three more skids and make a second box off one side of the first box. I remove the front skid off the full box and fork the material over into the second box. This effectively turns the pile and only takes about 5-10 minutes of much needed excercise.
Then I replace the skid and start filling the first box again. After it fills up, I take three more skids and make a third box off the side of the second box, remove the front skid off box #2 and fork it into box #3. Then I fork box #1 into box #2 and start filling it again.
When box #1 is full for the third time, I fork the stuff out of box #3 and run it over a frame that has 1/4" hardware cloth in it. This sifts if pretty nice. Anything left in the screen gets dumped into box #1 for a trip through the process again.
When #3 is empty, I fork everything in from #2, then fork #1 into #2. Box #1 is usually pretty rotted out by three months, so I smash up the skid and put it in a brush pile and build another box out of fresh skids.
This system has worked well for many years. I get so much dirt and compost out of this system that I cannot use it all in my garden, so I just pile it up in the back yard. We've lived in the house for 10 years. Last year I spread out the pile into a berm along the back of our property. It ended up being 4 feet wide at the bottom, two feet high at the top, and 110' long. That's alot of dirt from primarily kitchen scraps, bush trimmings, leaves and garden waste! /forums/images/graemlins/grin.gif
I also have a few piles that I just dump stuff on and let rot for a year without doing anything to them except for the occasional turning with the forks. That works too, but the three bin system is much more efficient and productive and only takes about 10-20 minutes once a month.