There are two key ways of making sure that your work can be easily understood by other editors collaborating on the article. One method is the “edit summary”—a text box that appears below the window where you’re editing the text of the article itself. Any text written here will be saved in the article’s edit history, and will appear as a brief description of your edit elsewhere on Wikipedia. So, for example, you might type in a phrase like “expanding paragraph that describes his service in World War I” or “adding references for claims made about the date and place of birth”: you want to choose a phrase that is short enough to be read easily, but descriptive enough that it will be of use to a collaborator who wants to know how the article is changing.
The other method of communicating your intentions is by leaving comments on the article’s talk page, which is linked to at the top of the article. You can edit the whole talk page, or a section of it, in just the same way that you edit the article. The key things to remember are that, unlike the article, on the talk page you should not edit or remove things that another editor has written—to preserve the whole history of the conversation, everyone’s statements should be left in place. Also, it’s important to “sign” your statements so that it’s easy for editors to know who is speaking. Signing a statement on the talk page works like this:
Once you’ve written down what you want to say – an explanation of a recent edit, a question you’re hoping someone can answer, a suggestion about how you think the page should change, etc. – finish by typing three or four tildes, like this. ~~~~ The tilde usually shares a key with the ` character, and can often be found in the top left corner of your keyboard. Three tildes ~~~ will automatically insert your username. Four tildes ~~~~ will insert your username and the date and time that you left your comment.