Load your vehicles up with food and water. Bring plenty for you and others. Fill your packs with it and break bread with others.
FOOD is the secret to great turnout at any event. Food means you can party for a LONG time! Eating food together UNITES people as a family!
Proteins and fats are critical, and carbs will help those not used to walking all day keep going.
Clean water is super important too.
Armies march on their stomach!
Also if it’s cold nothing beats hot food and drinks, My recommendation is some kind of European surplus mess kit (I like the German style ones cause it has a pot and pans ) and a small esbit or gas stove. You can cook pasta, soup, bacon, beans, pancakes, ect in that thing. Also one pede with a coffee pot could improve the morale of a dozen people near him if you bring some styrofoam cups.