To create a new branch in SVN, its very simple.
svn copy <source> <destination> -m <message>
This will copy the SVN in the source folder, into a new branch under <destination>. Very simple.
More, in depth information can be found here: http://svnbook.red-bean.com/en/1.5/svn.branchmerge.using.html#svn.branchmerge.using.create