Introduce the activity using the example comic. Write 3-4 sentences on the board using your target grammar. For instance, for present progressive:
Calvin is making a castle.
He is holding a rock.
He is destroying (breaking) the castle.
Or for past:
Calvin made a castle.
He held a rock.
He destroyed (broke) the castle.
Pass out the comic sheets to the students. Have them write 3-4 sentences per comic.
You can make this an individual, pair, or group activity.
You can allow one of the groups to "win" by giving points for the most interesting sentences written or the most comics completed.