Any public notice required to be given under any of the provisions of sections 262.550 to 262.620 shall be given by publishing a copy thereof for at least one time in a newspaper published within the county and having a general circulation therein and if there be no such newspaper within the county, then in some newspaper having a general circulation within the county. Any notice required to be given to any council member shall be given by personal service or by mailing a copy thereof to the council member, provided that any council member attending any meeting shall be deemed to have waived service of notice of such meeting. No notice shall be required of regular council meetings or of regular meetings of the officers or of any special meeting of the council the date and place of which has been set and recorded in a prior meeting of the council. Any notice to be given to the county commission shall be given by delivery of a copy thereof to the clerk of the commission. Notice to organizations selected by the council to have members on the council and cities and towns entitled to have members on the council shall be given by delivering a copy thereof to the principal officers of the organization or to the mayor of the city or town or by mailing the same to the person to be served.