Factions
There are three(3) Factions. You must make sure you choose wisely because once you choose you Faction, there's no turning back unless you delete your character. You also must have be in the same Faction as your clan if not, you will not be able to team up with your clan. Here are the Factions...
Valor
Valor is a Balanced Army. They have medium powered weapon and medium level defense.
S.V.E.R.
S.V.E.R. is more or less a Freelance Army. They have very powerful weapons, but lack in defense.
Raven
Raven is a Hi-Tech Army. They have low powered weapons, but they excel in defense.
Now that you know about the Factions lets get into Squad Leaders. You must be Level 15+ to become a Squad Leader. Squad Leaders are responsible for Field Coordination. This job is very important as you will be guiding your troops. Not only would you be leading the fight, you'll be giving your troops bonuses too. Here's and example..
Squad Leader
Once you're on the field, press Select. this will bring up the TAC Map. On this map you set your beacon. Once set, your troops should know where you would want them to hit the enemy where it hurts. When playing Sabotage, you have point A, point B and point C. just point to one of these objectives and they would know where to hit. Remember those "Bonuses" I mentioned? Well, Squad Leaders have special abilities. Lets say You pointed your team to Point A. When you and your team are at point A, they'll gain bonus EXP depending on what you and your team do. Rather if it's killing, defusing, planting reviving or healing. This bonus EXP is call Frago Points. Not only will you and your team get bonus EXP, but you will also share your Abilities as well; abilities such as extra defense, immune to poison grenades, with stand explosives etc. In other modes, you be able to call in UAV's and Air Strikes.
Tips and Tricks
1). Make sure you have a different Loadout for every occasion. No matter if you're a sniper or a commando, you'll never know when you need to repair something.
2). Always heal your squad members and if someone heals you, say Thank You!
3). Pay attention to your Squad Leaders and stay close. For they give you bonuses and may keep you alive.
4). Always repair your equipment. Equipment such as oil towers, AA Gun batteries etc...
5). Communicate this is most important!
Well, I guess I've shared everything?! If you have any Tips or Tricks to share, post them.
Good Luck and Have Fun!