If you are more artistic than literary, you can take part in making the Xubuntu desktop look better by contributing artwork and helping design the various aspects for the next release of Xubuntu.
The Xubuntu team is usually planning or working on at least some artwork projects for the next release. These projects can be found in the Artwork section of the Roadmap and it is primarily encouraged to help the artwork team with these projects. There are sometimes other projects and contests where we invite the broader community to take part, so follow our blog and social media (twitter, facebook) for announcements. In addition to the projects, contributors can help improve the default icons and gtk theme.
If you wish to contribute new artwork ideas to Xubuntu, like for example new installer slideshow images, please send your ideas on the Xubuntu developer mailing list for discussion. Sending new ideas is especially useful from the beginning of the Release Schedule and before the UI Freeze, which normally is a month before the release. Please note that messages that contain large attachments will go into the moderation queue, so it’s encouraged to start with an introduction email without attachments.
If you have found a bug in the Xubuntu artwork, please see the bugs for xubuntu-artwork at Launchpad, or join us in the IRC channel.
If you have some artwork ready, specifically themes for Xfce, you can also send them to Xfce-look.org to make them available for a wider audience.