Go in when you can just start to see. Slip in. Walk slowly for about 50 yards, stop and be still. Ease on forward another 50 and stop. I'm going to make a video about this one day. I've killed most of my deer slipping through the woods. You have to be slow in your movements though. A deer can spot fast movement from a long way off.
I’ve been watching the Hunting Public a good bit. Those guys can flat out stalk a deer and they do it most of the time with a bow in hand.