The best way to get started with Subversion is to read chapter 2 (Basic Usage) in the excellent free Subversion book here: 

http://svnbook.red-bean.com 

If you are using a Subversion GUI client, you can follow along by using the graphical versions of the commands indicated in the book. Since ProjectLocker is managing the server-side elements, you can ignore any commands that begin with svnadmin.