Instructions for this activity provided in Spanish. 6 different situations are posted around the room. Students work in groups to come up with advice for each person involved in the situation, paying attention to who is talking to determine which type of command to use (tú, Ud., Uds.). They use sticky notes to post an affirmative and a negative command for each situation.
I always stipulate that they cannot repeat verbs that have already been used by other groups, so they really need to get creative and think back through all the verbs that they know. (I do this at the Spanish III level).
I usually then go over the sticky notes under the document camera so we as a class can make corrections together, focusing on if they correct command was used, based on the subject. Sometimes students come up with some pretty creative pieces of advice.
Depending on your class size, you can have a lot of great examples. In my class of 15, we did 5 groups of 3. This resulted in 10 commands per situation (60 total for all situations).
Microsoft Word doc, so easily editable to meet your students' needs.