(adsbygoogle = window.adsbygoogle || []).push({}); This guide will show you exactly what classes you will want to use, and a little bit on the roles you will want to take up and how you will want to play. I put this together myself and will add to it if need be. Enjoy
[multipage=Playing With a Team]
Ask anyone and they will say that playing with a team is better than alone. Hopefully, this guide will take your team one step further, so you can own pretty much anyone. Interested? Then read on!
[multipage=Player 1]

This player will be the rusher who doesn't mind about K/D. He will be the one who provides a constant Spy Plane for his team and will block the enemies radar when required.

Recommended class:

SMG w/ Rapid Fire
Python w/ Speed Reloader OR Ballistic Knife

Semtex
Concussion x2
Jammer

Hardline Pro
Steady Aim Pro
Marathon Pro

Recommended Killstreaks:

3 Spy Plane
4 Counter Spy Plane
8 Blackbird

Basic Tactics:

Rush enemy spawn, 2 kills for Spy Plane, you will want to spray from the hip. Knifing is also recommended so a default button layout may be a good option. The ballistic knife is helpful here as is Steady Aim Pro. The Jammer is to place in the enemy spawn so you can avoid claymores and they cannot pinpoint where you are.
[multipage=Player 2]

This player will also be a team player, but will be focusing more on the objective then getting killstreaks.

Recommended Class:

SMG/Assault Rifle w/ Grip/Rapid Fire/Grenade Launcher
China Lake/RPG

Frag
Decoy x2
C4

Flak Jacket Pro
Hardened Pro
Tactical Mask Pro

Recommended Killstreaks:

4 Counter Spy Plane
5 Napalm Strike
6 Mortar Team

Basic Tactics:

This person will be planting bombs, defending flags and capturing headquarters. Flak Jacket and Tactical Mask Pro will help you achieve this, plus the grenade launcher + launcher secondary will aid you in the defending of positions when in a high position. The C4's will also help you do this, and in domination should be placed on your spawn flag. Hardened Pro will help you shoot through bomb sites plus the Napalm and Mortars should be saved for when you are far away from a point and need to defend a flag for example.
[multipage=Players 3, 4 and 5]

These players will be your slayers. They will kill enemies and try to build up air support to help the team out. These will be high killstreaks and these players will have the best K/D, so should probably be the strongest players in the team.

Recommended Class:

This is all about personal preference, but my recommended class would be

Assault Rifle w/ Dual Mags
Python w/ Speed Reloader

Semtex
Nova Gas
Motion Sensor

Hardline Pro/Flak Jacket Pro
Hardened Pro/Sleight of Hand Pro
Ninja Pro

Recommended Killstreaks:

8 Blackbird - This is a must!

Then chose 2 from:

7 Attack Helicopter
9 Chopper Gunner
11 Attack Dogs
11 Gunship

Basic Tactics: These people will generally stay in positions of advantage, using Motion Sensors to locate close enemies. They will also back up Player 2 (the bomb planter) and can take over if necessary. They should build up killstreaks as best as they can, so a Blackbird can keep going for as long as possible.
[multipage=Player 6]

This will be your stealth and air support player. He will always run Ghost Pro and a silencer. He will also be the first to pull out the Strella-3 missile to take down enemy air support.

Recommended Class:

Galil w/ Suppressor AND Dual Mags
Strella-3

Frag
Concussion x2
Jammer

Ghost Pro
Warlord Pro
Hacker Pro

Recommended Killstreaks:

4 Sam Turret
5 Napalm Strike
8 Blackbird

Basic Tactics:

Basically, get behind enemy lines and kill them, using the Jammer with Hacker Pro to disable then convert enemy equipment. Destroy all air support with your Strella and Sam Turret.