You should click link in your e-mail (or copy it to the browser address bar) and form for the last step of registration process should appear. In this form you should supply your personal details. Not every field is mandatory, but please supply at least your first/last names. Do not forget to set password to login to the conference site later. Click "Save" button to finish registration.
Registration information is shared between other conferences, so that you register only once and later can login to any conference supported by this system.