They like a bit of cover. If there's a vein of small pines or brush, or even a tall log or rock fence, they like to break their outlines. Hear noise, look for antlers at the edge of a big tree or other cover.
you don't need to go in deep, get in enough in the right spot quietly to do so.
Keep yourself vertical moving arms swaying boides bust you.
Approach any new area of view like your going to shoot a deer. Get you head in view very carefully and slowly. I like the woods to have a minute of peace before I peer over the ridge.
Deer love to bed in south faces. Deer do get nocturnal somewhat. They need need, they get it by moving and eating. when they rest, they enjoy the sun on them.
Want to improve your hunting 1000%, scout in the early winter with snow cover, take notes where brushy spots are, where water is, where spots are tougher or easier to pass, what trees.
Deer like a commanding view. Zig zaging carefully and slowly over a ridge without being too visually busted is ideal.
Test your gun in low light. Maybe temporaily paint the front and rear sights, or just the rear. Polish the front brass sight. A rear sight custom positioned for your eyes is a huge plus. Don't be afraid to relocate the sight. Many old guns have 2 or 3 different rear sight notches adjusted for new owner or moved a little for aging eyes. There's a art to iron sights, learn it. Read "the big lie" It's a military competition shooting book. Still hunter is good too. Salerno brothers makes a good DVD on them too. Kind of a local NY celebrity hunter without the glamour of those fancy hunting ranches.
Layered clothing. A good underlayer warm enough to slow walk on flat ground. Unzip the jacket when climbing hills. And then another layer when you rest. Sweat means your going too fast. I don't like bags, I keep everything in pockets.
I place wooden seats at break points in my hunting spots. I am part of a private 800 acre paper pulp company lease, so I have a brushy forest preserve to myself, literally. The other guys absorb themselves with atv's on the 350 acres in a corner, I get the other 450 or so to my feet. The worst spots for ATV's are the best ones for deer.
Make some natural deer blinds make a frame you have a sturday gun base, them break your outline with branches. Don't scent up one blind too much. Maybe alternate between a couple.
Spot and stalk is what I like. I got my places to rest, but take my time to get there.
Squirrel hunting is excellent practice for deer hunting on the ground.