Search through the documentation, the forums, and the blog posts. You can conveniently use this search box to search through all three at once:

In most situations your question has come up before in the forums or been documented in the frequently asked questions section. (If your first search does not return helpful results try rewording it several times.)

If you have searched through the documentation, blog posts, and forums but simply cannot find an answer to your question, the next step is to post a message in the Zotero forums. Zotero's developers as well as many advanced Zotero community members read and respond to forum posts. By asking questions in the forums you access the broader experience of the Zotero community, and also make solutions publicly available for other users who may have the same questions.