A lot of beginning artists focus on character drawings, neglecting backgrounds, settings, locations. A lot of beginning writers focus on dialogue, sometimes ending up with scenes of "talking heads". This is a challenge to improve on that.
There is no "post every day" rule or anything like that, just pay more attention, or make a greater effort, than you usually do. If you make something you want to share, post it somewhere with the tag "Settingtember".