I'm a pretty average player and I'm rocking a 4.8 K/D in TDM right now. I typically like to play games that have more of an objective than just getting more kills than deaths but they took out my favorite game mode for the time being. I also didn't want to play dom solo...But since this post is about raising kill to death ratios, TDM makes the most sense.
- Staying alive is more important than getting a kill: This is the most important concept you need to accept. What is more important to getting a high k/d (2+), a kill or a death? A death. You need at least 2 kills to make up for any deaths. Simple concept, but many fail to realize it....seriously.
- Do not get into gunfights where the enemy has the advantage: If they are head glitching behind a wall you need to flank them, frag them or call them out to a team mate. Don't be tempted pop your head out. You may be feeling lucky, but in the end, the house always wins.
- Get field objectives (but refer back to 1&2): Completing a field objective gives you a free kill streak. In these care packages I have gotten a kem strike, mortar strike, helos and other goodies. Field objectives can be as easy as getting a head shot or **** the last enemy you killed. And as an added bonus I believe you get a squad point for each objective. (I can explain how objectives work if anyone is interested).
- Use the environment to your advantage: This is more important than in previous CODs. The environment is filled with intractable objects. Doors open, gates open, walls collapse, train cars move...I am finding more and more of this in each match. My last match I ran in a building for cover and an X popped up. I hit it and a door opened up. An enemy was crouching with his back against the door...free kill. After the kill it also gave me an awesome line of sight to where the other team was camping.
- Learn to use the lean feature: I literally do not believe I have lost a gun fight when leaning in anticipation for an enemy. It surprises enemies...and it's hilarious when a teammate runs by, stops, and comes back to look at your character because they had no idea you could lean.
- Use your point streaks effectively: Tips for the 3 point streaks I am familiar with.... Do not call in your sat com unless your teammates already have sat coms up. One sat com is at best, a bad version of a portable radar. 3 sat coms create a uav, 4 create an advanced uav.... If you have a dog, do not trust him to watch your back. For some reason he is better after you die (martyrdog). I have found the best use for the dog is if you know an enemy is charging at you. Wait 2 steps to the side of a doorway. The dog will stand at the entrance and actually see the enemy.... My main tip for the sentry is to put it on a vantage point of a high traffic area and defend it's rear. It will in turn defend your rear. Pro Tip: use killstreaks you can consistently get and fit your game mode. High killstreaks are nice, but are limited by kills in tdm. By the time you get a big kill streak the match will probably be ending.
- Do not give the enemy a chance to shoot you from behind: I was lucky because the first soldier I unlocked came standard with 2 motion detectors and an IED (which is basically a bouncing betty that you can stick to walls and other objects.) Most rooms have 3 main entries. You can cover one with an ied, one with a motion detector and one with your gun. Throw them a few feet outside the entries so you have time to turn around when they are set off. When you need to move, move with a map border to your side.
- Amplify: 75% of the time I know an enemy is coming up behind me before they trigger any equipment. This is the best perk there is for getting an advantage on your opponent. Most people do not have dead silence unlocked yet. You will hear enemies running with wooden klogs on from about 25-30 feet. You can distinguish if they are above you, below you or even with you. Pro Tip: on the radar "^" means above, "v" means below...it is not the direction they are facing.
- Use the right gun: SMGs, sniper, shotguns and side arms are not designed for high k/ds. You need weapons with range, but can also operate in close quarters. I recommend **** rifles. I used the SC-2010 for a while and then switched over to the AK-12. They both work well. With the attachments I use the SC has less recoil, while the ak has better damage. Pro Tip: Choose your shots, do not fire unless you know you can finish them, and remember to tap the trigger if the recoil is going crazy.
- Use the right attachments: The obvious first choice is muzzle break. It gives you higher damage at longer ranges. If you want a high kd, you want most of your gun fights to be against enemies who are running at a medium to long distance from you. With that being said, range is more important than ever. These maps are fairly large. There are no small maps. Even the smallest map has multiple long lines of sight. My second choice (which I don't recommend for everyone) is the hybrid thermal scope. At long range you can see people who you normally wouldn't be able to see. I have been out snipping snipers, all day. Then when you hear someone coming with Amplify, switch over to red dot and wait for your unsuspecting victim to come stomping in. I also use the red dot when I'm navigating enclosed areas and medium sized areas. The thermal is meant for long lines of sight. Pro Tip: Incog will allow you to stay hidden from snipers, thermals and target finders..so while you can see them across the map, they will not see you).
I had a bunch more to add but I don't want to bore you guys with a novel. Let me hear some of your tips so I can try and keep this k/d rolling through the weekend.