rather than hide behind bushes, sit back into them facing out, so you have something to blend into. if you are under a big tree with ground cover around it, or nestled into a blowdown etc, you can blend in a lot better than sitting behind a bush with your silhouette against the sky. Sitting in more shade than the deer will also help hide you better. Just don't stick out like a sore thumb, survey the area for the most adequate cover to back into.
If you shoot right handed, you want more shooting lanes/pockets to your left and straight ahead. And angle yourself so the expected deer travel areas are in those lanes and you are downwind. Sit down and look around for the most open pockets to shoot through, they will still probably have some stuff in the way. Snap the small bushes and weeds and branches out of the way in 2 or 3 spots, leaving clear but small openings to shoot through. Remember the arrow comes out 2-4 inches below your sight. I set up for 20 yard max shots... I want there to be trees and bushes for the deer to walk behind so I can draw, and then have them step into a wide open pocket for me to shoot through.
Pay attention to wind and keep in mind you're not 20 feet up where your scent can blow over a deer. If a deer is downwind, it will smell you.
Also, make sure the cam on your bow won't touch the ground or your leg when you are sitting. So don't slouch and remember this when drawing back on a deer. Clear the leaves around where you sit so you can adjust without making noise. Draw your bow and move it left and right, and make sure there is room for your bow in front and your arm/elbow behind you. Only break the branches you need to move, but don't remove all your cover.
I like to have the bow sitting on my lap, or if there is a sapling next to me, I can lean the bow up on it. Quiver removed, lying to my right. Usually I hear a deer coming before seeing it, so I can get the bow up and ready to draw.
When it comes to a deer standing there in range and it's time to draw, just use your instincts, don't draw when the deer is in the wide open looking toward you, remember if you can see its eye then it can see you. Deer can't see that well, but they can see movement very well, so drawing back is what will get you busted. If you hear a deer coming and know it's going to come into an opening, draw before you can see it. Better to let a little buck walk at full draw than to have a deer you want looking right at you. If it passes a shooting lane and goes behind a tree or bush, draw and wait for it to step into the next pocket... like I said, just use instinct. If the deer hears a squirrel and looks away from you, draw back quickly. If the deer is broadside and feeding, might or might not see you, then draw slow and smooth and hold the bow steady.
I usually prefer sitting in a tree, but have killed a couple from the ground. The last 3 times I hunted, I bow hunted on the ground and all 3 times had a deer in range that never saw me. I never drew though, they were all little bucks. I killed one earlier this year sitting under a tree behind a buddy's house.
Good luck, it's not such an impossible feat as some people would say... I think I am starting to get a feel for it myself.
Here's the video of my ground kill this year:
https://www.youtube.com/watch?v=xNxhmv7rz5s
