WW1 Propaganda poster?!? Help?!?

I have to do a project for history in which i have to make propaganda poster. I have a choice of doing something about conserving food and materials for soldiers or i have a choice to do an anti-german propaganda about either zimmerman note, submarine warfare, or the kaiser!!! plzz help!!! I need some ideas on how to set it up because i have no clue what to do!! Thx!! BTW this is WW1!!