I dont think anyone can answer your question correctly without knowing where you hunt and what you hunt with. In general if you walk slowly thru the woods and jump a deer you cant just aim for the nose or worry about the wind.

You should have the scope somewhere around a 4x setting and pick your shot, most times if you are in the woods you have to use openings to shoot threw. Any of the mentioned methods are good for practicing. You need to be fairly confident with shooting offhanded with your rifle. The situation is always changing though so there is no answer someone can give you that will always work. Most times when I jump a deer it runs away from me and not left to right from me, So the best you can do is aiming at the front half of the deer. Ive shot bucks running straight away in the butt, with the correct bullets\gun they are still lethal shots.

I mainly hunt hardwood mountain terrain in WV.When Im not hunting out of a tree stand(broadside take you time shots can use about any gun)then I am slowly walking threw the woods. It seems to work best on windy days because my movement is hidden a lot better and it seems like you can walk right up on them compared to a still day. After or during rain is a good time too because it easier to walk quietly. I think Rifle choice does matter when you hunt deer you expect toshoot running. I use a Ruger Deerstalker in 44mag. Its an autogun, its about the only time I think you need a quick 2nd and 3rd shot for deer is when you jump them, there are other rifles that work good in this situation also just depends on what you are comfortable using.

Im no expert about hunting this way but I can tell you that patience is very important, take your time and walk slow, remember you can never kill a deer with the gun slinged across yourback, so make sure you carry it so your ready to shoulder it very quickly. Practice by finding something in the woods like a downed tree or rock break or whatever stands out and shoulder the gun and see how quickly you can get it in you sight picture. Up to about 100 yards or so I can pick out whatever and throw the gun up and its in the scope, thats mainly from practicing throwing up the gun and aiming at something.