First, register as an Artweeks member (as an individual or as an organisation).
Then, to enter an exhibition you will need your contact and venue details (including dates and times), a strong image (preferably square) for the printed festival guide, an accompanying 12-15 word description and a short paragraph to accompany the on-line listing.
Once you are a registered Artweeks member, you should upload a biography, an image of yourself/an artist at work and six images for your free on-line gallery.