Pretty simple concept, take 50 graveyards. This one could take awhile as there are up to 40 people you have to compete with (you have to personally cap it) plus any number of enemies who may try and stop you. If you want to play dirty and get it, let one person go in ahead of you and distract the graveyards guards and while he takes them down you can cap it. The key here is that you don't have to hold it... you only need to assault it, so don't worry about death afterward.
Straightforward but not all that easy. The main trouble I had with this one was assaulting or defending things before the other people did. Once again, on the assaults, you don't have to hold anything you just have to assault. I would suggest going on the offensive to start. As soon as you have assaulted a tower and graveyard fall back to your side and defend one of each. You can even just assault a tower and then fall back as you can easily assault a graveyard on your side that the enemy has taken.
Win 1 / 100 AVs. Want a way to do this, look at my strats... and hope to God the majority of the people in the BG are not idiots.
Even if you are not going for achievements, holding both mines becomes very important during a turtle so this one should be a given. If you are really going for it then you can always guard 1 mine. Usually you will only get one enemy at a time and between you and all the mobs in the mines it should be easy to take someone down.
Simply buy one of the AV mounts. They are bought for 50 AV marks. THey are sold by a vender just outside the old AV caves in Alterac Mountains or in the base of your faction in the BG itself. The alliance cave is located north-west of Southshore, just across the border between Hillsbrad and Alterac. The horde cave is directly north of Tarren Mill.
Win an AV without losing any tower or captain and control all the enemy towers. The key to this will be a strong defense. You must start your defense off at your factions captain to stop their initial zerg on him. Once you have saved your captain you must fall back and defend your towers but keep an eye on your captain to ensure you don't lose him. Your towers can not even be contested at the end of the game to get this. Normally I would suggest letting the enemy take a tower and you recap after they leave, but for this you can not risk that. You must hold every tower at all costs and if they do take one you have to take it back asap. The other part to this is controlling the enemy tower i.e. destroy them. You have to destroy them, not just contest. With your strong D in place just send a small group up that can hold their towers until they are destroyed, stealthers are nice for this. Graveyards, mines and enemy captains have no affect on this one.
This one is just to earn exalted with your AV faction. There is rep from almost every action in the BG and it is given to everyone in the BG regardless of where they are. So the way to get this is simply play, win or lose. There are, in addition to that, some quests that can be done for rep.
Kill fifty people in your base, specifically to building your leader is in. They key here is that it does not matter where you are, only where the enemy dies. So if you are, lets say, stealthed near your base and an enemy dies inside with your leader, you get credit. As long as you are in range for the honor kill, you get credit. That being said, the most common way to get this is to simply get a group of people to defend your leader.
Win AV in 6 min or less. The ONLY way to do this is to zerg. You will need most of your team including a strong tank and heals to just rush the enemy leader and take him down asap.
Kill someone while they are mounted in the field of Strife. You do not need to personally get the Killing blow on this one, you just have to be in range for the honor kill when they die. The key to killing them while mounted is burst; kill them so fast that they don't even bother trying to dismount.
Loot the Autographed picture of Foror and Tigule. This is an RNG achievement. The pic can drop off ANY lootable mob and player in AV and has a very low drop rate. To have any chance of getting this one in a short order you must pretty much just spend you time looting bodies. Just follow behind the main group of your team and loot everything as you go. Make sure you have some spare bag room as there is a lot of other crap you will get by looting these bodies.
Defend 50 towers. Simple. For this one you will want to stay on your side and be a general defender. Once the enemy has assaulted a tower you go and try to retake it. Wait too long and they will destroy it. If you are going in a group, let your group distract the enemies while you retake the tower. Once again you must personally be the one who defends the tower.
Complete all the listed achievements. Once you get your last one you will get this which counts toward the Battlemaster achievement.
Well that wraps up AV achievements. Have fun!