This is one of the features brought by the upcoming 4.1 Patch.
It's currently in its testing phase, thus can be buggy.
Anyways, if you have been experiencing issues with finding the appropriate guild, these times are over. With the Guild Finder you will be able to find a guild without having to post on the respective message board of a guild.
Let's now have a closer look at the new feature and its user interface!

By pressing "J" (Default) the Guild Finder window will open. In order for the feature to function, you need to be guildless.
Settings Tab

As you can see there are plenty fields to be filled out.
Guild Interests
What do you aim to accomplish in the game? Why are you seeking for a guild ? Questing ? PvP or even raids? The choice is yours to make!
Availability
This indicates when you're available in-game. You can choose whether you play on Weekdays or over the Weekends.
Class Roles
This is the role you will fulfill. There isn't really anything else to say about this.
Comment
You can insert whatever additional information you may regard necessary by evaluating your application.
Browse Tab

If you switch over to the Browse tab, you can see a list of guilds, who are seeking for new members. There you can see the guild rank, the amount of members and so on. If you choose a guild, just click on the "Request Membership" button.

Then another tab will open (as seen in the screenshot above) where you put a comment and send the guild membership request.
Requests Tab

Requests tab is the last one to mention. There you can see the list of your requests, how much time is remaining to accept or withdraw your request. You can even cancel your request by clicking on the red circle.
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