So you want to edit Wikipedia?

Here are some ways you can get started editing Wikipedia without having to dive headfirst into writing an article.

Text updating/improving

Text edits are one of the easiest things to get started doing. There are a whole group of people on Wikipedia called Wikignomes that make small fixes and there is a whole list of simple tasks that need doing. To get started all you need is an account. Almost all Wikipedia pages are editable, though some are protected or can only be edited by users who have seniority. An edit usually has three steps

make the edit
preview the edit to make sure it looks like you want it to
add an "edit summary" so people understand what you did (and mark it "minor" if it's something small like fixing a typo)

Many users interact with Wikipedia via their "watchlist" which is a list that shows them changes on the pages they are watching. Many users add every page they edit to their watchlist so some pages can sometimes seem like they are "owned" by a user because that user may show up a lot of you make a change to a page they are watching.

You can get started by editing your own user page. The Wikipedia editor has a text-based version using Wikipedia's markup, called the source editor (cheat sheet is here) and a WYSIWYG version called the visual editor. There are a lot of things you can do to customize your environment (including setting things like your pronouns) in the Preferences section.

Citations

Citations are what Wikipedia is built on! Every good citation you add to Wikipedia helps make Wikipedia better. The #1Lib1Ref project is all about getting people to add citations.

Citation Hunt can help youfind an article that needs a citation on a topic of your choice:
Citer can help you make many kinds of URLs into a Wikipedia-formatted citation, or you can use this tool for Biomedical citations

There are many other citation tools, not all of them will be helpful but they might be fun to look at.

Images

Images can be tricky. If you are uploading an image with a free license, put it on Wikimedia Commons so more people can use it. If you are uploading something that is usable because of Fair Use (Wikipedia calls this non-free media), it may need to be uploaded to Wikipedia. If the image isn't one you created yourself, or isn't published online with the proper license, there's a whole process that needs to happen involving the Open-source Ticket Request System.

If an item is published online with the right license (i.e. many library archives or Flickr sets), or if you KNOW the license, you can use the Upload Wizard. You will need:

the source of the image
the author of the image
the license for the image (can pick from this terrible list)
the date of the image (exact or approximate)
a description of the image
a category to place the image into

Here is one of many help pages on the subject.Wikipedia:Uploading_images

On your own

If it turns out editing Wikipedia is a thing you enjoy, there are more resources you might like

An intro page that gives you more in-depth information on each of the editors
a one-hour Wikipedia Adventure (tutorial) that covers the basics