Isn't that what you're supposed to do?
Warm-up, including a few fun drills - ladder drills (can use cones), slaloming through cones (with and without ball) etc.
Ball skills - the usual suspects, leading up to a game of Possession.
Be inventive but keep it simple. Ensure everyone participates, use group work, explain the activity clearly, don't just focus on the talented kids etc.
King of the ring is a great game for a warm up, also try Traffic cones(have a green, yellow and red cone and assign actions to each where the kids jog around) but try and make each action a fun skill like doing a different trick for each, football volleyball is good as well but maybe try throw head catch.