A foil balloon for enabling a user to print a customized design on each of its sides comprises a carrier (e.g. paper) comprising a central opening, and an upper second foil and a lower first foil releasably attached onto top and bottom surfaces of the carrier respectively. A valve is provided between the first and second foils and is disposed correspondingly to an inner edge of the opening. A heat sealed portion is formed around the inner edge of the opening on each of the first and second foils after heat sealing the first and second foils together with the valve being sealed by the heat sealed portions of the first and second foils, and perforations are punched on each of the first and second foils at a position between the heat sealed portion and the inner edge of the opening.