Okay, I'll take a stab at answering your questions. I'm referencing from Storey's Guide to Raising Chickens.
Roosts should be 2x4s flat side down and should have rounded edges. Allow at least 10 inches space for each regular-sized chicken, 12 inces for larger breeds.
Place the bottom roost 24 inches from the floor and at least 18 inches from the parallel wall, and space them 18 inches apart.
If floor space is limited, step-stair roosts 12 in. apart vertically and horizontally, so chickens can easily hop from lower to higher rungs.
Nests:
You should have 1 for every 4 hens.
For regular hens (leghorn type) size should be 12 in.W by 14 in.H by 12 in. deep
For heavy breeds: 14x14x12
They should be 18-20 inches from the floor and should have a perch just below the entrance so they will have a place to land before entering.
Place the nests on the darkest wall of the coop. Construct a 45-degree sloped roof above the nest boxes to keep birds from roosting on top.
Hope this helps. Let me know if you have any other questions.