I don't know that there is an easy answer to that. There are a lot of different ways you could compost. You can get one or more of those barrel tumbler composters or even make them from 55 gallon barrels, either metal or even better from plastic. You can just pile it up and forget about it. It will eventually break down. You can build bins and turn it regularly to speed up the process. Lots of different ways.
Then you get into balancing the greens (nitrogen) with the browns (carbon). One challenge you may have is that green grass clippings and pure chicken poop are greens. You really need some carbons to mix with them to get proper composting action. Most of my carbons are refuse from the garden, like dried sweet potato vines, corn stalks, dead bean vines, dead tomato vines, things like that. Some people use leaves. The bedding from your coop is a good carbon source. All my non-greasy non-meat kitchen wastes go in too. I think those are mostly greens (nitrogen).
Moisture is important. You want it damp but not wet. It's better if the weather is warm. You can get as technical and scientific about it as you want or you can be like me and take a much more laid back approach.
One way to manage volume is to use a droppings board to catch a lot of the poop when they are roosting. This keeps it from mixing with your bedding so you have to change out the bedding a lot less often. You'll be amazed at how much poop you can get from 11 chickens. If that poop builds up too thick in either the coop or in the compost bin and gets wet, it will draw flies. You need to mix it with other stuff to keep it from getting too thick.
What I have is two bins made out of leftover brick that are each about 4 feet square. I keep my active working compost in one and collect the stuff for my next batch in the other. The garden refuse is stacked in a pile for use as needed. I sometimes use grass clippings as well.
If you really work it, turn it often, keep it the right moisture, and get a good balance of greens and browns, you can maybe get a batch of compost in about two months. Mine take a lot longer since I don't work the greens-browns balance that tightly and I don't turn it that often. I sometimes let it dry out too which really slows it down. But if it is too wet, it can get slimy and stinky due to anaerobic action setting up.
