One thing that has worked for me in the past.....
If you are spotted by the deer. Duck down and hide for a minute. Then peek back up carefully. Some times they stay put and go back to feeding. Sounds weird but thats how I got one a couple years back. Or if they start to trot off whistle really loud and in my experiences they stop and look at you giving you a chance to do your stuff.
Sniper training 101. Move slowly from one tree to another, take about 5 min. before you move to look around real good. Let the deer make the move so you can see him. If you make normal noise like you hear in the woods, deer will hear it but will usually ignore it Unless you move or they smell you. Old man told me once- If they hear you, its ok. If the see you or smell you shoot quick. Better yet, buy a horse- cover up scent, transportation, stand and friend all rolled into one.
I found siome natural trails that the deer walk on allot so it was clear of weeds etc... at least moreso than the rest of the woods, nice for walking quietly.
Here is a little trick to use in your stalking tool box. Wait for the animal, especially deer, to have their head down and eating the local greenery. When they are chewing their food, it is like one of us eating a bowl of cereal. That crunching in their head helps to cover any sounds that they might otherwise detect in your movement.