Sha'tari Skyguard Reputation Tips
The Sha'tari Skyguard is a faction related to the Sha'tar that is closely associated with a special epic flying mount, the nether ray. There are other reputation-based rewards as well, such as epic trinkets. Once you reach honored reputation, you will have access to a free direct flightpath between the two Skyguard camps in Terokkar Forest and Blade's Edge Mountains. While using this flightpath, you get to ride a nether ray, as a preview of what you will look like when you get your very own.
A combination of daily and one-time quests allows you to raise your reputation from the starting state of neutral all the way to exalted. You do not need to have 300 riding skill to do any of the Skyguard quests or to purchase the Nether Rays at Exalted. You will need 300 riding skill to ride a nether ray, however.

To begin the process of befriending the Skyguard, talk to Yuula, who is located near the flight master in Shattrath City. If you have the requisite 225 riding skill, she will send you out to slay Gordunni Ogres in the Barrier Hills, which are only a few seconds by flying mount from Shattrath City. Once you've slain the requisite number of ogres, Yuula will be impressed enough with your prowess to recommend you to the Skyguard camp of Blackwind Landing.

Blackwind Landing, Terokkar Forest
This camp is located southeast of Shattrath City, north of Skettis near the river's fork. The entire region is surrounded by impassable mountains, so the only access to Blackwind Landing and Skettis itself is by flying mount. From this outpost, the Skyguard launches attacks against the arakkoa of Skettis - and they're looking for new recruits to aid their cause. The questgivers in the camp offer an assortment of one-time quests, which may lead to group quests with powerful rewards.
There are also two daily quests in the area that yield reputation through Exalted:

Fires of Skettis
This bombing run quest, which starts from Sky Sergeant Doryn, involves destroying Monstrous Kaliri eggs with the provided Skyguard Blasting Charges. Fling bombs down at the clutches of eggs until you've destroyed the required number. Look for the platforms high up on the trees, as they have an abundance of eggs. Usually you can destroy multiple eggs with one bomb if you aim correctly. However, it's all not quite as simple as it sounds...

The key to completing this quest efficiently is avoiding the dreaded Monstrous Kaliri, who make a living of knocking players off their flying mounts and sending them plummeting. When one of these ornery birds spots and attacks you, their attacks have a chance of dismounting you if they attack from behind. To make matters worse, they can also hamstring you, impeding your ability to evade them. Strafing around them, so that your back is not exposed, is one way to shake them off. Changing your elevation rapidly, by climbing or diving, is another method.

Escape from Skettis
This escort quest starts from a captive Skyguard Prisoner, who can spawn from three possible cages in the treetop platforms of Skettis. You have to escort him safely from the platform, defending him from any arakkoa he wanders too close to as well as others that spawn in. The actual escort itself can be much easier than simply starting this quest in the first place...

Only one player can be doing this quest at a given time, so when there are many players attempting to do the quest the first one to find the Prisoner wins. Once you learn the location of all three platforms, you can fly between them until he reappears at one of the locations. It's possible, and a good idea, to do this quest in a group as the entire group gets credit for the rescue. In addition, like all escort quests you may encounter an additional obstacle on PvP realms - enemy players.

Skyguard Outpost
The second quest hub for the Skyguard is found in Ogri'la, which is in the western section of Blade's Edge Mountains. There are more one-time and daily quests you can do here for Skyguard reputation. However, to unlock them you need to be neutral with Ogri'la, which itself is unlocked by completing an associated group quest chain, and then completing the Ogri'la quest "Our Boy Wants to be a Skyguard Ranger." Talk to Grok in Shattrath's Lower City to start the Ogri'la quest chain.
There are two daily quests at Skyguard Outpost that award both Skyguard and Ogri'la reputation:

Wrangle More Aether Rays!
This quest has you catching five aether rays to bring them back to Skyguard Khatie. Once you find one, you need to damage it until it's almost dead - then wrangle it with the provided Wrangling Rope. Use caution when using damage over time spells and effects, as they may finish off the rays before they can be wrangled. In addition, there are often a lot of other monsters around the rays so you need to be careful pulling them to avoid extras.
Once you capture a ray, it will follow you around on a leash. You can hand in the rays individually or in groups - turning in a total of five will complete this daily quest.

Bomb Them Again!
The second daily quest is another bombing run similar to Fires of the Skettis. This time, the targets are Fel Cannonball Stacks. Look for the glowing green stacks of cannonballs near Fel Cannons. However, while you're trying to bomb them, the cannons will be shooting at you. If hit, you'll fall off your flying mount, which could have a spectacularly bad outcome if you're high enough in the air. If you survive the landing you'll still have a damage-over-time effect on you that might finish you off, so be careful.

Essentially, you need to keep moving at all times while in the air to avoid cannon fire. Wait for the bombs' cooldown to expire, then dive down and chuck one down at a cannonball pile. Then immediately turn a different direction and climb out of danger!