We have a Java/Web team with several Java developers and a web designer. The "developers" handle everything from the database layer up to the sending of pages to the browser (using JSP pages). The "designer" is responsible for image creation, skinning the pages using CSS and tweaking the JSP pages to make them look "right".
Another problem is source control - our designer, after several years, still refuses to do merges in Git. He typically will put his code in a feature branch and send an email to the development team saying "branch so-and-so is ready to merge."
This problem could probably be solved with some simple guidelines like "All team members should perform their own source control maintenance" or similar general rules. But we don't have any.
What are the general rules that could be applied in this situation?