Increase your FOV to 85-100, make your crosshair to a large pink dot, play with your sensitivity until you’ll have a comfortable aim and settings, toggle sprint, play the assault course, do your missions and play every game mode at least once in a day (to get more credits-dirty bomb money), don’t use quick abilities (press 4/5 and then aim with your mouse, it is recommended to throw packs using quick abilities tho), practice movement and have some game sense about unpredictable movement and movement improvising, use voice commands to alert teammates rather if you need health/ammo/backup or just taunting the enemy team 
(the voice command for a medic is: V,2,1 and the one for the ammo is V,2,2), try unlocking an engineer (proxy,Fletcher,bushwacher), if you need anything just ask me and I’ll be there
My list of tips
Use your quick ability buttons for proxy however.
And learn the maps so you can move fluently.
Another thing, only one person can repair/defuse at once. So, so many new players do this.
Try to have a squad that contains: 1 medic, 1 engi and 1 assault or recon or fire support. A good mix for pubs.
Pay attention to your surroundings, don’t just focus on what’s in front of you.
There might be someone who needs ammo, or need reviving, or need healing, or some backup to repair the EV…
…or seeing those little devices that explodes and dispensing salt to yourself
…or those spotting devices
…or enemy’s camp point that previously killed your teammates so you could coordinate some airstrikes to flush them out
…or even the Objectives
Seriously, pay attention.
I see that “tip” every time when I look on a youtube tutorial for Dirty Bomb or when I read topics like this one. I don’t know if this tip is actually an important one because in every free rotation you will get one of those engineers for 2 weeks to play with. So far, in last 8 weeks we always got 1 engineer mercenary of 3 merceraries that we got for free in rotation. So basically better save your credits to buy one of mercs that you really like. If you keep playing this game for maybe 10 weeks you will pass through all mercs for free and you will know which one suits for you and with which you are bad. Those mercs that you like, you should buy (at least in the beginning).
Some tips for who to buy first:
You may only get vassili, rhino, nor aimee first, if you hate life and everything in it. You can get them later, once you can hit stuff. Hey, if you already can hit stuff, it’s up to you.
You don’t have to get a medic if you don’t want to; Aura works just fine.
If you like explosives, I definitely reccomend Nader or Fragger.
If you want to get an engi first, get proxy or bushwacker, fletcher has a higher skill ceiling.
If you like being cancer, it actually doesn’t matter who you buy first. You can be cancer with ANYONE. (but proxy does it pretty well)
Wut? Y tho?
I binded quickbuttons to mouse4 and mouse5 and it works as intended
At this point after I bought Proxy I feel like the game is VERY orientated around engineers, like it’s so much easier to earn top score with them, even if you kill less stuff.
I got Fragger previously and I like him very much, shooting, fraggin etc and I perform OK, kill stuff, blow up stuff and push, I don’t die too much, I usually end up with like 5k score while TOP guys get like 15k (3-4 of em),
and with Proxy you just jump around the map at the speed of light, plant mines for newbies to step into and do objectives and at the end even if you got killed 10+ times in less than 10 sec right after spawn (ran into bullets) you still get about the 90% of top score ~ 13k… it’s just sad, I don’t want to be a cancer, but it’s too easy as one 