Help:Editing

Use A Sandbox
For major overhauls create a Sandbox (a subpage) in your userspace and copy the page code to the Sandbox and edit it there until you have a finished product. Then copy from the Sandbox to the original page.

You can create any number of subpages and they are perfect for Sandboxes, to-do lists, etc. For more on subpages, see this help page.

You should also use subpages/Sandboxes when working on new pages until they are at a useful state. This way incomplete and/or confusing information is not presented to a reader.

Always Provide An Edit Summary
You can force the web app to prompt you if you submit a change without an edit summary. The option is in Preferences -> Editing Tab -> Editor section. Check to enable "Prompt me when entering a blank edit summary."

Pro tip: Be careful using Wikitext in the summary as it will be rendered when viewing the "History" page.

Clean Up After Yourself
If you move a page and create a redirect, you should work through everything that links to the redirect page and point those links to the new page so that eventually the redirect can be deleted. This helps avoid spaghetti redirects.

In the "Tools" section of the main menu on the left is a special page: Special:WhatLinksHere/. Following that link on any page will provide a list of all pages that link to it.

Archiving Pages
Never "blank" a page, or clear all content to effectively delete a page. If an item or feature has been removed from the game, there is a process for archiving the item or feature. Instructions are here: Help:Removed_Items. See also Help:Deleting.

Editing Syntax
In addition to the Wikitext examples below, you can also insert HTML into pages.

Only at the beginning of a line:
de:Hilfe:Bearbeiten es:Ayuda:Edición ru:Справка:Editing