My buddy and I got a wild hair one Wednesday night in college and headed for Nebraska the next day to chase speed goats. We hunted out of DB blinds, and did a lot of stalking, as well as a lot of running for miles trying to shoot one of those things. I will say that hunt was far more exhausting than the two elk hunts I went on. I ended up shooting one on a stalk, and my buddy missed a few.
If I go back again I will have my first pin set at 40 yards and be able to shoot out to 80yards. It's easy to stalk within 80 yards of them, but you don't get much closer than that. I got lucky and shot mine at 40.
Like everyone said, you will be in your underwear within about an hour of sitting in the blind. You just about lose your mind. Turkey hunting I can sit all day long. Sitting in a double bull in 90 degree weather tests you to the fullest no doubt. Ameristep makes a nice portable fan that hooks to your blind hub that might be worth looking into.
Definitely buy a good pair of Knee pads, and learn to shoot your bow with leather gloves. Those prickly pears will just about kill you when you are stalking.
Look for places they are crossing fences like Blake said. They don't like to jump at all. You don't need to worry about brushing in the blind. They are just like turkeys, they don't mind them at all. Granted they can smell though. So you need to be cautious of the wind. Make sure you have the netting up as well.
Antelope are the worst smelling animal you will come across. It will be a fun hunt, we went from dawn till dusk each day. You just got to keep trying. Sitting on water holes didn't really work for us because it wasn't that hot out and it rained a ton during the trip, so they didn't really need to drink. Goodluck