Far from being a pro, but I have had some success from time to time. Still hunt turns into spot and stalk quite often. I move really ssllooww, stopping often for a while, and watching for movement both with binoculars and my naked eyeballs. I try and use shadows, folds in the terrain and any other cover that can keep me hidden. Some stalks after spotting may take a long time; I missed an antelope earlier this year after a 30 minute stalk, and I originally spotted him about 200 yards out. Got to within 15 yards before I managed to totally flub the shot, but the stalk was great.
I have taken several turkeys with still hunt/spot and stalk, in fact all the turkeys I have taken with one exception have been with that method. Here's one from last year.
I have taken a few deer through that method, too. Here is one of them.
I practice in the off season trying to get close, and most of the time I am armed with a camera. These elk were trailed, heard, and then spotted and stalked this summer. Too bad they haven't played the game during the season.
Obviously, hunting the wind is critical. Last week, the only elk that I saw in 4 days of hunting came ghosting up behind me in some black timber. I had been standing still for probably 5 minutes, and he got to within 20 yards when I saw that nose come up, and he backed out the same way he came from. I'm pretty sure he never saw me, but he sure did smell something that wasn't to his liking.
No better or more fun way to hunt than still hunting, if you ask me.