Well, all those are helpful tips. Based on my own practice, I have few additional tips to give you.
1. Create meal schedule and stick to it, so the child gets used to having food at the same time a day.
2. Avoid giving snacks closer than 1 hr before big meal and no later than 1 hr before going to bed. This will improve quantity of food eaten during meal and decrease storage of excess calories before night time
3. Make meal a social event, i.e. eat with the child or encourage others to participate...child will be more interested in food if he/she sees others eating also
4. Offer finger foods and make it fun, like making smiling face from eggs and bacon, or flower from vegetables plate
5. If the child wants the same food three-four days in a row- DON'T discourage it. Kids are picky eaters overall and if the food is healthy and well balanced...there's no reason to protest
I hope this helps a bit
Yuliya