Know whether any of your guests have food allergies. If so, be sure to provide options that are safe for them to eat or let them know that they are welcome to bring their own food.
Be realistic about how much food and drink to provide based on the length of the party. A party that is planned to be an hour or two might only require refreshments and birthday desserts, while a party that is meant to last for several hours will need more of a meal.
Make sure that you plan for enough food and drink to cater to all of the guests. Remember, get too much food rather than too little.