These tips could be used for snipers or anyone who wants to have another skill under their belt- stealth. These tips are for snipers and spec. ops not campers.
1. When walking, plant your toe first. Then, lower your heel softly. When you're running, just lightly bounce off your toes. This will make you move quicker with less of a chance of landing on a noisy stick. NOTE: Don't run when you are nearby an enemy that doesn't know where you are.
2. Check thoroughly before moving to different cover.
3. If you're enemy is standing, they will tend to be looking around shoulder height for people. Depending on how long they have been guarding for, they might not even be looking hard at all! If your enemy has been moving and they are crouching, they will tend to look lower because they are lower. So if you are after a standing opponent, crouch. If you are after a crouching opponent, since crouching people are usually on the move, climb a tree or something to get a good view.
4. Hide your gun when peeking from your cover. It's a big object and makes you easier to spot. Only take it out if you found a tango.
5. When switching to a different cover (tree to tree), check everywhere while you do so. You will have access to views you aren't able to see otherwise. But, this doesn't mean stand there and look around for an hour. Just quickly scan the area and try not to be seen.
6. Pay attention to your surroundings, look for ways to walk where you blend in better. If you're wearing a woodland camo then crouch to be closer to dirt and leaves rather than walking in front of a tree.
7. Don't sit still and wait for them to come to you. Anyone can sit still and wait. You have to find a way to get to your target without be spotted.
8. Stay away from walking through open areas, if you are spotted you must be near cover to get ready.
9. Make sure you are going to hit your target before you shoot. If you miss, you made noise that will only make you easier to find.
10. Listen. If you hear a noise don't think it's the wind. Look diligently until you are sure nothing is there.
Hope this helps!