The legislative body of such political subdivision in question shall provide for the manner in which such regulations and restrictions and the boundaries of such districts shall be determined, established and enforced, and from time to time amended, supplemented or changed, and may adopt such ordinances or regulations as may be necessary to carry into effect and make effective the provisions of this chapter. No airport zoning regulations shall be adopted under the authority of this chapter unless and until the proposed ordinance has been published at least once a week for two consecutive weeks in advance of its passage in a newspaper of general circulation within the political subdivision, or, if there is no newspaper, then by posting the same in four conspicuous places within the political subdivision, together with a notice stating the time and place that the ordinance is to be considered by the legislative authorities, and stating further that at such time and place all persons who desire shall have an opportunity of being heard in opposition to or in favor of such regulations. No such regulations shall become effective until after a public hearing in relation thereto, at which parties in interest and citizens shall have an opportunity to be heard. Such regulations, restrictions and boundaries and ordinances passed under the authority of this chapter, may from time to time be amended, supplemented, changed, modified or repealed. The preceding provisions of this section relative to public hearings and official notices shall apply equally to all changes and amendments.