Trappernal,
I have not seen any drawings for "box" stands. There are just so many different ways to build them! First, consider how large you need the stand to be. If I am hunting alone, I think that 4' X 4' is big enough. It is a bit cozy, but I like the small size because you can see and shoot out of any window, without having to move around much.
If you will have someone hunting with you, at least a 4' X 6' will be what you need.

For most hunting spots, 8' high will be good enough, so I use landscaping timbers for the four legs. Use 1 X 4's to cross brace the legs.

For the floor and base, make a 2 X 4 frame, built to the size that you want, the 4' X 4' stand works well also, because the plywood sheets will already be the right width, and you won't have much waste either.

For the floor, use 3/4" plywood.

Next you will have to frame the four sides. I make four side frames out of 2 X 2's, I use 4" screws to anchor the sides to the base, and put about four screws along each corner, to tie the sides together. By putting the stand together like this, you can easily take it apart if you need to move it! When you are building the side frames, 2 X 2's will feel weak and flimsy, but when they are covered with the plywood shell and bolted together, the stand will be just as sturdy as if it were framed with heavier 2 X 4's!

I got a little ahead of things here, so while you are building the side frames, you will have to decide for yourself, how high you want the windows, and frame them in also. The higher you put them, the less likely the deer will be able to see your movements! Remember though, that if you put the windows too high up, it will give you an awkward shooting position.
Speaking of windows, some people build big windows that go the width of the stand, I prefer to have my windows only 18 to 24 inches wide, and about 9" tall, just tall enough to get a scoped rifle into shooting position. For window covers, use what ever you want,! From no covers, to plywood, or plexiglass, hinged, or sliding windows, fit to size.
Note here, that the better you fit the windows, the less leakage you will have into the stand to cause water damage.

The height of the stand frame can be what ever you are comfortable with, I usually don't go more than 6 feet on the stand sides. Slope your frame a few inches from front to back, for good roof drainage. For the roof I use corrigated fiberglass. Make sure to allow for a few inches of overhang on all sides. This, and good window and door fit, will keep leakage to a minimum, and insure that little critters can't make a home of your stand!

For the outer shell, I use the thinest plywood that I can find. 1/4 inch hardwood flooring underlay, is cheap, light, and when painted, will last for years. As I said before, with
2 X 2 framing, and light plywood covering, the sides will feel shakey, but when bolted to the base, screwed together in the corners and covered with the roof, it is as sturdy as if it were a metal frame!

I hope I have given you enough to start with, every time I build a new one, I learn things that will make the stand more comfortable, portable, and weather proof!
Good luck!