Bring your own dishes to barbecue and outdoor fetches
For my last big barbecue outside - in a barbecue hut (no running water) - I asked every guest (at least 40 people) on the invitation to bring his plate, his silverware and his drinking glass.
That is now 4 years ago and the idea has become so independent, that today in the circle of friends and acquaintances, the guests without cue start up with dishes, if somewhere outside is celebrated. No cardboard or plastic waste, no Hölzchenziehen to the dishwashing and for everyone the good feeling to have done a very small bit per nature.
If you can bring that in a nice or funny way in the invitation, (as well as the request for certain clothes), it is certainly synonymous with your friends and acquaintances well.
The image of the dancing barbecue spirit is one of the most beautiful of the celebration ... I have to post.