Last year Codership produced a lot of valuable content to help Galera users to get started with Galera and manage Galera. We have gathered the resources to our website.
Taking Full Advantage of Galera Multi-Master replication video can be watched here.
We have now uploaded Slideshare with many new presentations. Check them out!
The best source of multi-master Galera Cluster help, Galera Cluster documentation, is being updated constantly.