Ideally, 4 sq ft per bird in the coop and 10 sq ft per bird in the run. Less is possible for small and bantam breeds.
For bedding in the coop you can use dry leaves, dry grass clippings, hay, pine shavings and some say sand in a good option too (personally, I'd stay away from sand as it may cause respiratory problems). Bedding in the run can be dirt, but using one of the above will make cleaning and maintenance easier.
Nest boxes can be made practically from anything as long as the chickens feel safe and secure in them. Some provide curtains. They should be fairly dark. Access from the outside will allow egg collecting and inspection with minimal disturbance to the birds.
For ventilation you should have windows towards the top of the coop so there is no winter breeze or winds that can get them sick.