How do I get a Profession?

You have to find an NPC that can teach you their Profession. Ask other people where you can find certain trainers, or discover them on your own. The easiest way is to ask guards in major cities.

Using Professions

After you have trained or purchased a Profession, hit "P" to bring up your abilities book. Then, look for a new icon that has been placed in there for that skill. You can drag this icon over to your action bar to make it easier to find and use. If you can't fit it on the first row of your action bar, place it on a different row by left-clicking on the scroll arrows to the right of your action bar (it's ok if the icon is still selected on your cursor).

Professions

If you go Mining there are two recommended paths. Decide which one you want to take.

Mining - Mining is used to collect items for engineering and blacksmithing.
Blacksmithing - Create armor and weapons.

or

Mining - Mining is used to collect items for engineering and blacksmithing.
Engineering - Engineering is used to assemble cloth, leather, metal, and stones into parts needed to make explosives, guns, scopes, bullets, mechanical dragons, aquatic helmets, and more.

Herbalism - Collect herbs that can be used with alchemy.
Alchemy - The alchemist mixes herbs to generate potions with a variety of effects.

Skinning - Gather leather and hides for leatherworking, blacksmithing and tailoring (mostly leatherworking).
Leatherworking - Create leather armor and armor patches.

Tailoring - Create cloth items and bags.
Enchanting - Improve existing items.

Secondary Skills

First Aid - Healing.
Fishing - Collect food. Good for cooking.
Cooking - Food is used in the game to heal players out of combat so that they can return to the fighting as quickly as possible.

Gray - You cannot increase your skill by making these items or harvesting these items.
Green - These items give you a fairly poor chance to increase your skill. You can still do it, but its going to take a lot of gathering/creation to up your skill with these items.
Yellow - These items give you a reduced chance of increasing your skill. It's still pretty reasonable to try to increase your skills with these items.
Orange - These items give you your best chance of increasing your skill. For many of the Professions, making an orange item will always increase your skill.
Red - Your skill is not high enough.

Expert and above skill tiers for secondary skills require you to find the books to teach you them. Artisan level requires a quest to be completed.

• Some Professions allow you to use the trade screen to interact with other people's items. For example, enchanters can enchant items directly in the trade screen. Lockpicking and some other Professions can also be used via the trade screen.
• If you attempt to learn a recipe you already know, you will now see a message that says you already know it.
• Some recipes are intended to increase your skills in that Profession rather than to create an item to sell to another player.
• Some Epic items that can be created by players require reagents that can be obtained only through raids.
• Generally, recipes with white names are store-bought and ones with green or blue (or purple) names are drops from monsters. So if you see some white recipes for sale, a person just bought the item from a vendor and is trying to re-sell it for a profit

In the bottom left corner of the trade interface, there is an area where you can select how many of a specific item you want to create. This is very helpful when you're creating the same item repeatedly. There is also a "Create All" button that will create as many copies of the item as you currently have reagents to make.

Buy stacks of Profession components from other players. That is faster than collecting them on your own! Have your friends save up components too.

Devote a certain bag to carrying your Profession items. You can even pick a different-colored bag if you have one, to make it easier to find.

Know which classes will need the products that you can create with your Professions:

Mail: Warriors, Paladins (Hunters and Shaman can start wearing mail at level 40)
Leather: Rogues, Hunters, Druids, Shamans
Cloth: Mages, Priests, Warlocks

Know which Profession components to save while you are fighting. You can sell them to other players or give them to friends, rather than selling them to the merchants:

Blacksmithing: jewels, metal bars, linen, wool, leather...
Engineering: jewels, cloth, leather, mechanical items, metal bars...
Leatherworking: leather, ruined pelts, hides...
Tailoring: linen, cloth, wool, silk...
Cooking: meat, various monster parts...