I am creating my first project in Subversion. So far I have
branches
tags
trunk
I think I immediately need to make branches singular and sta
As noted by @victor hugo, the "proper" way is to use svn copy. There is one caveat though. The "tag" created that way will not be a true tag, it will be an exact copy of the specified revision, but it will be a different revision itself. So if your build system makes use of svn revision somehow (e.g. incorporates the number obtained with 'svn info' into the version of the product you build), then you won't be able to build exactly the same product from a tag (the result will have the revision of the tag instead of that of the original code).
It looks like by design there is no way in svn to create a truly proper meta tag.