Pursuant to the provisions of this Charter all powers of the City shall be vested in an elective Council, which shall appoint a City Manager, who shall see that the policies and legislation adopted by the Council are enforced and who shall administer all governmental activities and enterprises of the City. All powers of the City shall be exercised in the manner prescribed by this Charter, or if the manner be not prescribed then in the manner prescribed by ordinance. If no procedure is established either by Charter or by ordinance, then that provided by general State law shall be followed until the Council shall provide a different rule.