1.Sniping(Islands): Most people like to snipe on the rooftop, but are exposed. To prevent your death, go to the edge nearest the marooned ship. You`ll be able to cover most of the area, withoyt risking your neck.
1a. Sniper Prevention: If someone else is hiding on the roof and you can`t get the kill, there`s an easier way. With the stealth perk (or luck) go behind the building. It`ll be an easy kill met with little resistance. Just shoot them in the back.
1b. If the sniper still has you in his sights, keep moving. You just zigzag so you can kill them first.
2. Sniper Prevention (Any Map): Just set damage to low! The only way they can kill you is with a headshot.
3. Desert Eagle, the savior: Getting the 500 pistol kills may be tough, but it`s worth it. If you`re in a close ranged battle and your primary runs out, pull out your handy dandy Desert Eagle. On normal damage, it takes two hits to kill. On high damage, it only takes ONE. It can easily help you win the duel.
4. The Ladder Teleport: Found by yours truly, just the other day. I do not advocate glitch exploitation to win a match. Use it if you like. All you need is a weapon that can aim, and any MP map with a ladder. Go to the top OR bottom of a ladder. Walk to it and try to trigger the action button that says Use the Ladder. Aim down, and walk away to anywheres you like. Don`t run, or you have to repeat. Crouching or standing does not matter. Always keep your weapon on ADS. That means DO NOT reload. When you feel like it, tap that action button. Voila! You`re on the ladder. I haven`t tried, but it probably works in campaign too.
You`re welcome. I hope you liked these, and my newly discovered glitch.