Take and understand criticism – Accept the fact that there will always be players better than you. When you meet such a person, listen to what they are saying as objectively as possible. Be sound with your reasoning and logic. Sit from their perspective and figure out what reason they would have to criticize your performance. I rarely have problems with the people in my Guild, but if their WoW-playing is not up to par, the beast does get unleashed.
Recognize someone who is lying in game – There are many tools that we have at our disposal that helps paint a clear picture on the events leading to a wipe. The evidence does not lie. We know who breaks what sheep with what ability. We know who’s not healing certain players at certain times. We know people who aren’t respecting the capabilities of threat meters. The flip side of this, is, of course, to know better than to lie about something yourself.
Properly apply to a guild - There’s a certain art to applying for Guilds. They have their own methods and regulations that need to be respected in order to be properly considered. If there’s a template, be sure to follow that template. If you need to speak with a specific individual, make sure you do that, too.
Augment their gear – Priests don’t apply Agility enchants. Warriors don’t add +Spellpower enchants. Casters don’t apply Clefthoof patches. Know what stats are important for the role that you intend to fulfill.
Submit a ticket - There will be times in the game where you’ve accidentally sharded an important piece of gear or face a situation in which other players are powerless to help you. What you need to be able to do is submit a proper GM ticket. Ensure that your ticket has as much information as possible. Include important points like the approximate time of the incident, the names of all parties involved, what you perceived to have happened, etc. Make sure if there is a problem that you contact them fast.
Earn gold – There are multiple ways to earn gold. Dailies are now the most common, the next highest would be trade-related items being placed on the Auction House, and finally selling services via the Trade Channel. Know how to do some farming and place your goods for sale. Recognize good times to buy and good times to sell (Hint: When are most raiding guilds raiding? When do Arena points hit?)
Advertise in trade - Know how to properly advertise and how to ask for services. I commonly see people in trade chat ask for things very vaguely. It’s much more effective to add more detail. Specify what enchant you’re looking for so you can save time – “LF enchanter for Mongoose. Have Mats. Will Tip” will get a much better response than “LF High Lvl enchanter.”
Use the auction house – Understand how to utilize the auction house in such a way where you can recognize deals when you see them. When placing items for sale in the auction house, do not drastically undercut other players selling the same items. Understand the approximate value of what items are worth via supply and demand principles. There are a couple of mods out there that can help you with this – Auctioneer, BtmScanner, or Beancounter all have arbitrage features. Know how to work your server’s economy to your advantage.
Use the map and locations - Lots of navigation and travelling must be done in World of Warcraft for players to advance through the game. Understanding how to read the map properly and recognize coordinates is a huge thing that some players seem to have trouble doing. Know your compass directions. Try to have a general idea of how long it takes for you to travel to certain parts of the map.
Research and look up information - Other players are not walking libraries. Learn how to search up items, quests, and NPCs on the different search engine sites like Thottbot, WoW DB, and WoWhead. Being able to do this means you’re at least independent and sufficient enough to not have to rely on other people so constantly.
Use the /ignore function – Don’t waste time commenting in trade that someone is spamming, and don’t waste time talking to immature players who harass you for everything from run throughs to gold. Blizzard gave you the ability to never have to talk to these people again – know how to use it.
Control Aggro – If you constantly outthreat the tank and you fail to recognize this, you will pull aggro & die. Learn how to read addons like Omen and configure it in such a way that is of maximum benefit.
PvP – While this skill is not so common on PvE servers, it is nevertheless something to learn when you decide to dabble in a bit of PvP action. Learn what spells to use to escape, survive longer, and kill your opponents. Obviously the priorities here will vary by class. I know as a Priest I like to hold onto my Psychic Scream as long as possible. The point is that even if you don’t ever want to run through a Battle Ground or form an Arena team, you have to have some basic knowledge of how to defend yourself, because even on a PvE server, it will come up eventually.
Macros – The use of macros can help simplify actions in the game. They allow you to string numerous actions into a simple click or keystroke. If you’d like a quick primer on the use of macros, I strongly suggest checking out the introductory guide at Priestly Endeavors.