Our first steps tour and our frequently asked questions will help you a lot after registration. They explain how to customize the interface (for example the language), how to upload files and our basic licensing policy (Wikimedia Commons only accepts free content). You don't need technical skills in order to contribute here. Be bold contributing here and assume good faith for the intentions of others. This is a wiki — it is really easy.
Thank you for your contributions. Your image or other content was recently deleted, or will soon be deleted, in accordance with our process and policies, because it was not, or is not, within our scope. Please review our project scope, but in short, Commons is targeted at educational media files including photographs, diagrams, animations, music, spoken text and video clips. The expression “educational” is to be understood according to its broad meaning of “providing knowledge; instructional or informative”. Wikimedia Commons does not contain text articles like encyclopedia articles, textbooks, news, word definitions and such. Each of these other kinds of content have their own projects: Wikipedia, Wikibooks, Wikisource, Wikinews, Wiktionary and Wikiquote. If the content seems to fit the scope of one of those other projects, please consider contributing it there. Otherwise, consider an alternative outlet. If you think that the deletion was in error because the contribution really was in scope, you can appeal it at Commons:Undeletion requests, giving a reason why it fits our scope to help others evaluate the matter. Thank you for your understanding.