Pastors of a congregation are chosen and formally called by the congregation and examined by the presbytery, a body made up of the pastor and elders in a geographic region, to be sure that the man meets the biblical qualifications for the office and can demonstrate serviceable knowledge of the Bible and its doctrines. If successful, he is then ordained and installed to the office of pastor.
Ruling elders go through a similar process on a local scale; nominated by someone in the congregation; he is examined, undergoes a time of training and testing, and is then elected by the members of the local congregation.