The neutral auction house can become one of your best friends. Other players are constantly checking both factions' auction houses to find an appropriate price for the good they demand. Often times, goods are cheaper on the alliance because they have more people, thus, the supply increases as demand decreases and price goes down. If you are horde, feel free to transfer gold to your alliance toon through the neutral auction house in order to buy them item and bring it back to the horde side where it is more expensive. The 15%, as of patch 3.3.3 (down from 30%) is well worth the extra 50% or more you can easily make on one item alone. Blizzard decreased the neutral cut for a reason to 15%, that reason is to get trade facilitated between the horde and alliance. Make sure you take advantage of this! Tips when trading between factions:

I like his recommendations 2 level 1-20 zones to get to 20, then do all the 2nd zones since they are designed for walking (Horde: Northern Barrens, Silverpine Forest, Ghostlands, Azshara, & Hillsbrad Foothills if you need a little more. Alliance: Westfall, Loch Modan, Darkshore, Bloodmyst Isle, and if you need a little more Redridge Mtns, or Duskwood). Don't even bother with the higher level areas, too spread out. Finishing up a Monk now and I had done all these zones before the update, the running between quest and the 50% experience cap is driving me crazy.

 ":"  -  Any time a step ends in a ":" instead of a "." means that the next step is part of the current step you are on.  This generally means the next step should be done while working on the current step.  This means every "start working on" or "continue working on" will end in a ":".  But this is used with other occasions as well, so keep this in mind.
For example, the Azure Whelpling belongs to the Dragonkin family. However, it has Beast, Magic, and Elemental abilities in addition to a Dragonkin attack. Different attacks are strong and weak against different family types. Having a diverse spell selection might increase your chances of being prepared with a strong attack against an opposing team.
While the big NPCs of Battle for Azeroth have had plenty to do, the role of the player in the narrative is odder than ever. In the vanilla game, adventurers were faceless members of a larger army. We participated in great battles, but we were mostly there to shoot and loot. Burning Crusade and Wrath of the Lich King elevated the player, having NPCs marvel at us and thank us for our service. Later, in Legion, I became the Highlord of the Silver Hand and worked side by side with the biggest characters in Warcraft lore. I’ve run a garrison, saved the world, and I now hang out with the High King of the Alliance constantly.
Blood Elves and Dwarves gain access to Heritage armor as part of 8.1, as well, without a prolonged quest line, though they’ll need to be exalted through Silvermoon and Ironforge, respectively, in order to receive it. A Warfront called The Battle for Darkshore focuses on the struggle between Night Elves and the Forsaken. During the Warfront, you’ll be able to transform your character with temporary abilities, and when your faction controls either the Darkshore or Arathi Highlands, you’ll gain access to world quests.
For items that you can gather directly, you have the choice of either going out to gather them yourself or to buy them from the AH. The former adds no cost to your item but requires time and effort, while the latter can be quick and hassle-free. Even should you choose to get the materials yourself, don't forget to add them to your cost — your labor and time should be compensated for, even if just a little.
Cool the whlelping spot that has caused so much controversy int he gold farming community.  I still think spot is mentionable because it's really the only reliable spot to pull out a crimson whelping.  Most of you are probablly thinking this farm is old and beat to death, and you are right.  BUT that does not take away the fact that the whelping does drop highest from this farm.  If you can get it from the slavemasters your looking at anywhere from 25,000g and above.  A cool nifty old spot, that has survived the test of time.
There are times when you will be fighting things a couple of levels higher than your character. This is easy enough for some, but others might find that they need to be a bit more careful. If you let yourself get a couple of levels ahead of the guide then this ceases to be an issue. If you look through the configuration options you’ll see a place to set your difficulty rating.
You’ll get a small window inside the game with instructions for what you need to do next, every step of the way to 120. You’ll also get a waypoint arrow that points you in the right direction to go at all times. If this sounds extremely convenient, you’re right! Zygor’s leveling guide/addon has completely taken the frustration out of leveling for me, personally. No more reading comments on WoWHead about how to complete quests. No more getting stuck, frustrated and bored with leveling. And no more feeling like WoW takes too much effort.

Soloing an instance can be all the more profitable if your character is an enchanter. During any solo instance run, you'll end up with some items which can be sold or traded, and some that are bind-on-pickup. Non-enchanters can only sell these soulbound items to a vendor, but an enchanter can disenchant the bind-on-pickup rare items, and then sell the shard/dust/essence instead of just selling the blue item to a vendor. (A side benefit of selling enchanting materials is that they do not require a deposit to list in the auction house, allowing you to list endlessly until the item sells.)
One of the very cool things about Zygor’s Guide is that it’s automated. Not only do you not have to manually switch from game to guide, you won’t even have to click to the next quest. Complete a quest and the guide will automatically update to the next quest. The guide does it for you (usually, sometimes you’ll have to click to the next quest on your own.) It really is like having someone giving advice over your shoulder. Here’s the next quest, here’s what you need to get…
What’s worse, it’s rarely satisfying when you do make it to a new milestone in your grind to unlock the gear you need. Legion had legendary items that changed the way an ability functioned, which would also completely change the way classes played; the Azerite traits in the Battle for Azeroth are rarely as interesting. Instead, they are simply passive bonuses that, in most cases, help you do more damage without any extra effort on your part. While some classes are lucky enough to have traits that change their gameplay slightly, Blizzard has so far seemed to favor nerfing those traits out of viability for most specs.
Charge Into the Warfronts: Fight on the battlefields of a large-scale, 20-player cooperative Warfront to claim a key strategic location. Capture resources to build your faction’s forces, lead the charge as your troops lay siege to objectives, and fight the enemy commander to claim victory in this new PvE mode inspired by classic Warcraft RTS battles.

Once your character makes it to Outland and beyond, cashflow frees up considerably. The quest rewards are much better than in Azeroth. In fact, a typical character will earn from 1000-1200 in quest rewards and vendor trash while leveling 60-70 in Outland, and perhaps 1400-1600 from 70-80 in Northrend. The tendency is, therefore, to spend more freely after one hits 60. However, it is important for players not to go crazy on their spending once they make it to Hellfire. One thing is, training costs, repair costs, and consumable costs are also higher. More important, there is a large purchase that you are going to want to make at some point after level 60, your first flying mount and skill. The "bird" costs 40, the skill will cost you far more. Not only that, but if you want to fly it in Northrend at level 70, you'll have to shell out another 400 for Cold Weather Flying. And for those characters who will be 'farming' herbs or ore in either Outland or Northrend, an elite flying mount is almost essential, as it helps you gather almost twice as fast. That's another 5000 you'll be looking at. Therefore, budgeting carefully during the 60-80 leveling process is essential to ensuring you have sufficient cash on hand for making those purchases. Saving your pennies early makes that bird appear that much sooner.