As far as I know, this is a standard feature of Canny, so you most likely just need to enable it.
RSS feed for NEW entries, ideally different feeds per Board, but one combined feed will work as well. Ideally continuously updated, but once per day would work too.
Benefit: Find new posts directly, without needting to go through 12 boards manually and switch each of those to "new" (since "trending" as default is not really useful).