Start by slicing! The sausage and zucchini can be cut in to about 1/2″ thick rounds. I left the potatoes and mushrooms whole. Make sure your onion is chopped in to large pieces so they can be skewered in-between the other foods of choice. The corn was not the easiest to cut up (be careful!) so I would say aim for 1″ thick rounds.
Arrange on skewers and coat with marinade (olive oil, sea salt and pepper, Italian seasoning) on all sides.
Grill until done (about 10 minutes) making sure to rotate. Serve warm!