It's All in the Planning
Set your guests' arrival time just after your child's morning or afternoon nap. This will ensure that he's fresh and ready for an afternoon full of fun, excitement, and visitors. Keeping your decorations simple will also help your youngster enjoy the day without getting overwhelmed. Creating a relaxed, familiar, and fun environment for your child may lessen the chance of his becoming shy around guests, or spending the special day clinging to Mom or Dad.
At this age, stranger and separation anxiety can prevent youngsters from enjoying company—whether they are familiar people or not. Try to keep your list of guests to a minimum. If you have a large family (and this is easier said than done) consider setting aside a room for an adult and the youngsters to be in, and reserve another room or part of the house for your other guests to lessen anxiety for little ones. If you are planning a party outdoors, you can create the same comfortable environment for your child by setting aside a toddler tent, or fencing in an area so that the little ones can play under the careful watch of a parent.
Schedule your party time for about an hour and a half to two hours. This will allow plenty of time for fun and festivities, but will appropriately fit the attention span—and energy level—of most little ones.