M-x package-install marmalade
marmalade.el provides an Emacs Lisp interface to the Marmalade package
server. You can already use package.el to download and install packages in
Marmalade; this package adds the ability to upload them.
To use marmalade.el, you must set `marmalade-server' to the URL of the
Marmalade server to which pakages will be uploaded.
TODO: This should default to the main server.