Oekaki is Japanese for "to doodle". An oekaki board is a place where people can draw straight onto the internet using a Java applet. DDL has its own oekaki board that is free to join and easy to draw in! If you encounter any problems, first visit the FAQ and then email Kagami if you need more help. I may create a tutorial in the future, but meanwhile you can visit this wonderful one by n-m.com.
Remember to register before you begin drawing to keep track of your own artwork! Have fun! ^_~