What is it?
(What does it look like? How is it made? What happened?)
Keep your description/assessment of the artwork brief and meaningful. Look closely for meaningful details or key artist decisions that created the artwork, perhaps regarding materials; size; selection of participants; placement. Be selective; avoid over-indulging in minutiae, or producing list-like descriptions that are cumbersome to read and largely inconsequential to point 2.
What might this mean?
(How does the form or event carry meaning?)
Join the dots; explain where this meaningful idea is observed in the artwork itself. Weak art writing, making, and looking claim great meanings for artworks without tracing for the reader/viewer where these might originate materially in the work (point 1) or how they might connect to the viewer’s/readers interests (point 3.)
Why does this matter (to the world at large?)
What, finally, does this artwork or experience contribute—if anything—to the world? (Or, to put it bluntly, so what?)
Keep it reasonable and traceable to points 1 and 2. Answering the final question—so what—entails some original thought. And remember that the achievement of even good art can be relatively modest, thats okay.