How do I...

...edit anything at all?

You need to be logged in, and to get an account you need to request one to fend off spambots. If we're being really slow at approving you, try asking in the wiki thread on the board.

...create a page for a new quest?

In a separate tab, type the quest's full title, ideally as given by the author, into the search box on the left and hit enter or "Go".
Assuming it doesn't already exist (and you don't see it in the search results under a slightly different name), click the "Create the page" result at the top of the list.
Copy this into your new quest page:
{{subst:MakeNewQuest |author= |thread= }}
Fill in the author and thread number, e.g. |author=Weaver |thread=12345
1. Tip: add something like |description=Ruby, a herbivorous bunnygirl, wakes up with amnesia in an underground facility inside the braces to fill in the lead paragraph at the same time.
Preview and save!
Extra credit: Edit the page again and spiffy up the generated text.
1. If it's an image quest, add [[Category:Image Quests]] near the bottom, next to Running Quests.
2. Fill in the infobox completely. See Template:Infobox for documentation and examples on how. You might want to add a title image, and any discussion threads.
3. Add sections for characters, chapter plot summaries, and fanart. See below.

(If you want to do things manually, see Help:QuestTemplate.)

...change the picture in a quest's Infobox?

By default, the infobox will use the OP image of the first thread, which most of the time is a pretty good choice. But you can override it.

If you want no image at all:

Edit the page, and add this to the Infobox under the author:
|suppressimg=1
If there's an image set manually as below, you'll need to remove that too

If you want to use an existing image from the quest:

Edit the page, and add the post number to the Infobox under the author, like this:
|imageext=12345

If you need to use a custom image:

Edit the page, and add a line specifying an image name to the Infobox under the author, like this:
|image=MyQuestTitle.png
If this is an image already on the wiki, you're done. Else, make sure the file extension matches what you're going to use, and preview before you save to make sure you've picked a unique name (it helps to include the quest title in it).
Save the page, and click the red "250px" that shows up below the quest title in the Infobox.
Fill in the blanks in the image upload form that appears. It can be helpful to include the source of the image in the description, e.g. a link to the thread it came from.

You don't need to reduce the size of the image: the wiki will do it for you. It displays images at a width of 250px, the same as the board for the OP post of a thread.

...add a new thread to a quest's Infobox?

Most of the time, you just need to copy the last |thread= line in the infobox and change the numbers. The |thread1= numbering is important to the template and these numbers must be unique and in order, but if the quest numbers things differently you can use thread names, e.g.:

|thread2=5678 |thread2name=Chapter 2
|thread3=6789 |thread3name=Chapter 2 ''(cont.)''

Some quests might do really weird things with their threads that need special trickery. You can look up what each parameter does and how to use it at Template:Infobox. Remember to preview!

Discussion threads use disthread1 (and disthread1name) instead. They are numbered separately—there can be a thread1 and a disthread1.

...make a list of characters with portraits?

For each character, you want something of the form:

[[File:BobQuest Bob.png|thumb|left]]
==Bob==
Just some guy.
{{-}}

The [[File:…|thumb|left]] line includes an image, put on alongside the text. You can either upload pictures in advance, or save the page with missing ones as placeholders to upload later (in which case make sure the extension matches when going to upload).
- Either way, please try to include something like a short version of the quest title in the filename to make it unique.
- You don't need to shrink the pictures, but you might want to crop them to best fit the character.
==Bob== is a heading. Above all the characters you probably want a top-level heading called =Characters=, and maybe you want to break them down into groups. More equals signs mean a deeper heading.
Include whatever prose about the character you want.
Finally, {{-}} forces everything below this on the page to be put below the image if the prose is shorter. Without it, all the characters will bunch up together in a trainwreck.

You can use the same technique for a list of chapters with subtitle images.

...add fanart to a quest's page?

Use Template:Fanart, like this:

= Fanart =
{{fanart|857}}
{{fanart|798}}
{{fanart|515}}

All you need to provide are the numbers of the posts on questdis. For slightly more advanced cases, see the template documentation.

You don't have to upload the images to the wiki.

...mark a quest as abandoned?

If it only ever had graveyard threads, then it is a "dead" quest, and we take it off the main list:

Remove [[Category:Running Quests]] if present.
If it had an Infobox, add |dead=1 to it.
Otherwise, change [[Category:Quests]] to [[Category:Dead Quests]].

If it has at least one thread in questarch, we leave it on the main list:

Change [[Category:Running Quests]] to [[Category:On Hiatus]].

...rename a misnamed page?

Click the "Move" link at the top of the page, next to "Edit".
Fill in the new page name and why you're changing it.
If you get told you can't move the page, there might be something in the way. Ask for help in the wiki thread.

Don't just copy and paste the content to the new page. Using the move feature preserves all the history and sets up redirects so old links keep working.

...delete a page made by mistake?

You can't, but you ask to have a page deleted by putting [[Category:DELETE ME]] in it.

Reference material

Wiki markup

This wiki uses Mediawiki, so the full documenation is here. More usefully, Wikimedia offer:

Useful templates

Templates are invoked by putting just their name in {{braces}}. So to use Template:Stub, you add {{Stub}} to the page.

Infobox is used to do the nifty panel on the right with the quest details at a glance and links to its threads.
Stub is used to flag pages as being at an early, incomplete stage and in need of more content, like a plot summary or character list.
- (dash) is what {{-}} in pages invokes: it forces the next part of the page to be pushed down below any floated-to-the-side images. This is used to make character descriptions line up with their portraits rather than bunch up together.
Fanart makes a nice little box with a board image in, with optional caption. Use a bunch of them for a fanart section. Questart can be used for doing the same with non-fanart.
Spoilers marks a page as having spoilers. Since even new readers may want to visit a quest's page to get at its list of threads, try keep the introductory paragraph spoiler-free and put this somewhere below it.
Citeq can be used to make a small inline link to a thread when you want to support some fact on the wiki with a post on the boards. For example, murder mystery quest The Last Flight of the Sparrow made extensive use of these to help ensure our summary of the situation was accurate.
NSFW marks a section of the page as full of smut. So you're probably going to end up using it on a fanart gallery sooner or later.
Todo lets you put little visible markers in a page that something in particular needs doing, as a reminder for later or others.

You can also browse a gallery of notice-style templates.

Help:Contents

Contents