There comes that time in every players life where they queue into the battleground and find themselves adorned with the crown of raid leadership.
Knowing this you can either drop the raid leadership position into someone else's lap like it's some form of moldy apple, ignore the position entirely assuming that people will do whatever they want anyway or make the best of what you have and try to provide either information or guidance.
There's a lot of theorizing about what battleground strategies are best in what situations and what you should do if for example IB GY gets capped and when it is ok to cap the stables in AB. There's so many forum posts, strategy guides and blog entries about this you can probably make a series of books about it that would put SunTzu's art of war to shame.
Fact of the matter is that none of this matters (at least not right from the get-go). BG's are not about strategy, are not about tactical advantages, rouses, open ground, narrow passes or method and discipline. BG's are about people and as a raid leader that is what you have to deal with.
In any given BG you can find the following general groups of people:
1. The AFKers / Botters happily sitting at various locations on the map trying to not make it too obvious that they're just sitting around doing nothing
2. The Zerglings (term borrowed from starcraft). The people that rush into battle, charging ahead and generally trying to stay with large groups of people. They are where the honor is, and where the honor is in their mind is where the crowd is.
3. The BG enthusiasts are interested in winning. Some of them will pro-actively back-cap towers, ninja mines, recall back to base or organize some form of defence around flags or bottlenecks.
4. Last but not least there are the 'scrubs'. They're introducing their low level character to the battleground, generally are somewhat aimlessly looking around at what to do and if there are quests to be done they will happily skin wolves, collect armor scraps or try to cap mines.
The first thing to understand that whatever instruction you may want to give your raid will be ignored by the AFKers and the Zerglings. The scrubs won't have a clue what you're talking about (cap IB GY wut?) and the enthusiasts will probably take your instructions as a request, consider it and if it has merit act on it.
So the key to organizing or at least making an attempt at organizing a BG is trying to get the enthusiasts on your side. Zerglings have a tendency to follow suit. If all the enthusiasts are turtling around Iceblood for example a lot of the zerg will turn around and join the defense because they are well aware that the larger crowd tends to draw the most honor.
What to say/do, what not to say/do
As a raid leader you have to have an overview of battle, if you suffer from tunnel vision when you are in combat (focussing a little too much on your personal battles) then consider finding a somewhat more quiet spot so you can take a look at the map a little bit more often.
Participating in defense is probably the easiest way to do this. Holding flags, graveyards, bunkers, home base or other key objectives gives you plenty of time to analyze the situation and still be a valuable asset to your raid.
Once you're nicely settled into your position the second most important thing is to advertise status and request status. Mods like deadly boss-mod and similar allow you to see what objectives are currently being attacked by what side. Report this status to the raid on a regular basis (but not so often that it turns into spam) it will help everybody get a grip on the current situation. Make sure that when you report things you report things grouping them either by level of importance or by side. There's no point in spamming all the current caps that are going on. Report the important ones first (you get to pick which are important). Let it settle in and then report the rest of the objectives sorted by side (either all alliance ongoing caps first or all horde ongoing caps first). Information becomes useless if it's too much at once or when people have to look at their chat for longer than a second or two to see who is doing what and where.
If the rare case occurs that someone asks for a status on a specific objective make sure you give it. It makes the person who asked feel slightly less anonymous and all the more motivated to work towards a win.
Next to providing information it is also your job to collect information.
"Is Galv down?"
"Is Balinda still alive?"
"How many allies at the blacksmith?"
"Where is the enemy flag?"
Are all valid questions.
Keep your questions short, concise and free of emotions.
"WTF? Galv is dead? How did Galv die?" Is not the right question. Galv is either dead or he's not. Don't invite your raid to debate or comment. The more people stand around typing the lower your chance of success and the more likely it is that people will start acting like complete and utter idiots.
If you have obtained a critical piece of information then use it to weave it into new instructions and repeat it once in a while.
"Galv is down, incomming IB tower. Defend IB."
That way people know that galv is down (should they have missed it during the heat of battle) and know that they can expect pressure on Iceblood.
When giving instructions remind yourself that it has to contain useful information and only useful information.
"Allies are backcapping SP GY, offense hold SP GY then take Dun baldar north"
"We're losing SP GY, WTH are you doing? take it back!"
The way you say things is crucial. You're the general, you're leading the troops. You're not their highschool councellor. If people start argueing with you ignore them. If people start calling you an idiot ignore them. If people start commenting on your gear, the fact that you only have 8k HP and don't have any epics worth anything, ignore them.
You're going to take some fire as a raid leader. Ignore all information that is not relevant to the battle and focus on the information you can use and that is worth repeating.
"OMG WTF our RL only has like 8k HP, loser go enchant your gear"
'The lumber mill was taken by the alliance'
"Haha we're being led by a noob, we're so going to fail"
"STFU and kill stuff retard"
Out of those 4 lines only one is relevant. Ignore the random insults. Highlight the facts and respond once again in a clear and concise fashion.
"LM has been taken by the alliance, how many allies at LM?"
The next step in dealing with people and information is to motivate people to say something when they're in trouble. Nothing puts a bigger dent in a well-oiled offensive than your defense slowly crumbling without informing anyone.
"Report incoming alliance by numbers"
"Call out incoming if you need help"
These are things that can be repeated once in a while. The more people give a clear indication of what is going on on their end the more control you have over a battle.
It allows you to be reactive. If allies are moving in by the bucketload on Farm (AB) then they must've left LM / GM / BS and ST undefended for the most part and you know that with a quick offensive move you can possibly cap 2 to 3 objectives while the allies are standing around at farm waiting for the cap.
The final piece of the puzzle is to commend behaviour you want, and ignore behaviour you don't want. Never call anyone out on their stupidity, they will argue their stupidity and the stupid in them will take over raid chat.
If people call incoming and then manage to mount a proper defense tell them.
"Good job defending Farm, move to BS"
A simple GJ or thanks can go a long way in providing the right atmosphere.
Even if your Raid is losing the match, stay professional, stay clear and stay focussed on the battle. "You are all retards" is not going to help anyone.
There is always something that can be done to gain that last little bit of honor, be it defending a tower or zerging an objective to squeeze out another 60 honor a person.
Find those objectives and motivate people to execute them.
Once you grasp the basics of how to deal with the people in your raid you can then and only then consider strategies.