This goal has the following fine print specified by roeder25:
Anything that facilitates grading counts. This includes making rubrics, creating an entry in Skedula for assignments, downloading and waiting for Unity projects to open, and anything else that can be reasonably tied to grading assignments.
If I truly have no more grades to do at a given time, I can count lesson planning, paperwork, creating assignments, bulletin board production, and similar teaching-related responsibilities.