The little things matter, too! A lot of our articles could use some style, grammar and spelling changes, or even a full makeover. You could also make redirect articles for common alternate names for an article.
A lot of articles are imprecise; for instance, they often refer to events without giving a specific date or time frame. You can help by finding such imprecise articles and adding dates and other details; don't forget to reference your sources! (Preferably, use footnotes in a "References" section, or add inline external links after the statement being sourced.)