Just make sure if you are playing in a team, make sure that everyone knows the callouts for each map

communication is key to doing good in mlg games. buy a mic and play with people you communicate good to. do call outs. dropshot. headglitch. camp.

Get a good controller. I just bought a scuf controller. It helps with jumpshotting because it has paddles on the back of the controller. It also has trigger stops which help you to get more shots out on a single fire weapon or a burst fire weapon. And get a nice headset you can here enemy footsteps really well.

Make sure you know all the callouts on the maps..

1st Buy a Scuf competitive controller
2nd Buy a gaming headset (Astros A40,Trittons)
3rd Have a GREAT team
4th Make sure they know callouts and spawns for certain game modes.
5th Dont leave the team if you guys do bad. Learn together!
6th Never give up like step 5.

Make sure you have good aim on your shots.
Call out in the tea, where you are and if you die tell them where they killed you.
then you should build up on your gaming, and then in a couple of years to come, hopefully get known.

My top 3 facts:

Get used to the right sensitivity. e.g. 10 is perfect since this means you react very quickly and doesn't limit you in anything e.g. reactions, but if it's too high, go to 9, and keep going down like that, until you find the right one. (But as I said, 10 is ideal).

Get comfortable with different types of weapons e.g. Automatic, Semi-Automatic and Burst, as each of them suit different maps than others etc.

Get a good headset e.g. Turtle Beach or Tritton (made by MadCatz USA). This means you can hear footsteps better than you could if you were listening out of a TV and in turn will give you the advantage over players with a bad headset/no headset at all.

1. Good Equipment
2. GREAT team players (No 1 man teams that do all the work)
3. NEVER give up (Have a bad game? Practice what the other team did to you to beat you.)
4. PRACTICE A LOT

You'll probably need a high quality headset. If you're playing S&D only, you want to know all of the lines of sights, sprays and best places to defend the bomb. If you're playing MLG variant then, learn all of the different callouts and tactics for those game modes. Also, you want to have a good team around you.