Contact area theme parks, museums, arenas, theaters, and restaurants that cater to children, and find out about their programs for parties. You’ll also need to meet and check out clowns, magicians, balloon artists, singers, and other entertainers you may engage. You have to know what’s hot and what’s not in the fickle world of children and match the age group of the party to the right theme.
Post flyers and ads at community centers, schools, and retail outlets, including party supply stores to publish it out. Retailers may be willing to allow you to advertise at their stores if you promise to shop for supplies there. Place ads in newspapers and shopping guides. Ask friends and acquaintances to spread the word about your services; offer a bonus or a discount on future services for business they send your way. Do the same with satisfied customers. You can also contact companies in your area that plan holiday events (Fourth of July, Christmas, and the like) for their employees; offer your services to organize separate entertainment for the children.
In other side, you also should think about the expenses of the business. The principal up-front expenses are for advertising and promotion. Charge by the hour for your planning and supervision of the event, and add the cost of any supplies you must purchase or rent; you should be able to buy at wholesale or discount prices and resell at retail prices. Your client can pay entertainers and food providers directly, or those services can bill you, in which case you can use a cost-plus basis for billing for your hours, adding a markup to other costs.