My design of a large size (~2 cubic metres) composting bin for the cold composting of garden waste. It can also be used for hot composting and I have done this previously with access to a compact tractor and a mix of horse and chicken manure, turning the mix a couple of times to help it break down quicker by incorporating oxygen to feed microbes.

Basically you need some corrugated sheets of tin and a star picket for each corner. The tin is level and squared to the rest of the bin as you go, to keep the front door working at the end. You can use tek screws to fasten the tin to the star pickets, as many as you feel necessary for the strength of your bin.  For the front of the bin, don’t tek screw the front sheet of tin, instead add an extra star picket, as you can just make out in picture, which forms a sliding door for easy access to the material, both putting it in via a wheelbarrow and removing it. Just insert the sliding panel and whack in the star pickets to create a smooth opening and for the bin to be shut securely.