Stealth: also known as stalking. You "stalk" your target and get in a position to take them out.
When you do this, take your time. Be observant of your surroundings and always listen. If you hear something, decide the best thing to do. If what you hear is shooting, you should probably start running or you should jump behind cover. If you hear some shooting in the distance, you might be able sneak up and pick off some of the guys who are fighting.
In order to be able to hear the things around you, you will have to be able to move quietly yourself. The best way to do this is just to take your time. Avoid walking over dead leaves, noisy twigs and thick brush.
It takes time to get good at stalking. Just keep practicing!
Marksmanship: Being able to accurately and efficiently take out your targets.
This also takes practice You should get a scope, and adjust it, to be able to hit your targets with hopefully only one shot.
You will also need to consider what kind of rifle you will use.
If I am playing with one or two people, I like to use a bolt action sniper. They are really accurate, and don't make a lot of noise when you shoot them, so if you are able to see your enemy first you have a great chance of being able to sneak up on them and take them out with one shot.
Another great option is a gun like an M14. This is a semi-automatic sniper rifle so you can fire more shots more quickly, where with the bolt action, you have to pull the bolt back after every shot. M14's do make a little more noise, but I think it is ok since if you miss the first shot you can quickly fire again and take them out. I like this kind of gun in bigger games because if there are people everywhere, you can be stalking someone and someone else will all of a sudden start shooting you out of nowhere, and you will be able to return fire more effectively with a semi-automatic rifle than a bolt-action rifle.
Tactics: Tactics are pretty much deciding what to do in any situation to accomplish your goal and hopefully not die.
As a sniper try to stay out of the open. Other people have a lot more firepower than you, so avoid getting in major fight. Try to ambush, stalk, and pick off.
Be patient! find places with both concealment, and cover. I like to find a place with solid cover at my back, and good concealment in my front, and a good field of view that I can see. This would be the perfect place, but you cant always find a place like this, so just do your best.
When you find your place to hide, make sure you have one or two escape routes. You will want to be able to escape quickly if you get spotted and attacked by someone with a machine gun.
I hope these tips are helpful!
As a sniper try to stay out of the open. Other people have a lot more firepower than you, so avoid getting in major fight. Try to ambush, stalk, and pick off.
Be patient! find places with both concealment, and cover. I like to find a place with solid cover at my back, and good concealment in my front, and a good field of view that I can see. This would be the perfect place, but you cant always find a place like this, so just do your best.
When you find your place to hide, make sure you have one or two escape routes. You will want to be able to escape quickly if you get spotted and attacked by someone with a machine gun.
I hope these tips are helpful!