Its not much more complex than just putting the file in your shared folder. When someone does a search that contains your file's name, it will show up on a search.
If you really want to share something - effectively, that is - then go onto IRC, find a channel that's serving the kind of file you are sharing, then use a bot such as sysreset to serve access to the file.
But, in answer to your question, as far as I know, you just place it in your shared folder.