Write a proposal that is equivalent in style (formatting, etc) to a CHI note, and 2-3 pages long. You can follow all of the advice on that page except that you may expand the contribution somewhat beyond what would be
expected for a note (since you haven't done anything yet, this won't impact the length of the paper much) -- you are aiming more for the equivalent of a CHI paper.
Write a presentation. Presentations will be held on Thursday, 9/16, and you will have 10 minutes each to present plus time for swapping/questions.