There are different types of defense strategies that can be chosen from, one is to sit in a corner and watch a door that people will come running through to try to kill you, also known as camping which I do not choose to do unless I'm on a high killstreak. Another defense strategy is to play objective based game modes, such as domination, demolition, or capture the flag, and keep moving your position around the objective to protect it from the enemies that will be working their butts off to get it taken over. Either way you are camping and you might receive hate messages for it, but it's part of the game, people always complain about campers but sorry, in real life I wouldn't be the guy to go running through the middle of the war-zone guns ablazing.... I would be the one that stays in cover the whole time. Just because it's a game doesn't mean you have to be stupid about things, it's still a war, and if you want to level up fast and have positive k/d's each match then I would choose to play defense more.
My favorite Assault Rifle to use is either the m4a1 or Acr6.8 with the attachments proficiency and use Silencer/red-dot sight or silencer/heartbeat sensor. As a secondary it all depends on you, I personally like to use either the mp9 akimbo or fmg9 akimbo. For equipment I use Semtex/Flashbang, to slow incoming enemies down and to kill enemies that are hidden behind cover that I can't hit with my Assault riffle. For perks I use Sleight of hand/Quickdraw or assassin/then marksman or dead silence. For killstreaks I use the specialist strike package, and for my first perk I get assassin if I don't have it selected already and then dead silence if not selected already, then scavenger in case I run out of ammo while getting on a good killstreak.
Tips to playing defensively:
- Make sure you always have a full magazine in your gun, never know when/how many enemies will turn the corner
- Pay attention to your UAV so you know if enemies are close
- If your partner dies by you be ready for an enemy to turn the corner
- Always be behind some type of cover so you have an advantage over incoming enemies