When you come to the Church to be married, you are asking the Catholic Church to accept you and allow you to share in its vocation and the Sacrament of Matrimony. The Church welcomes you and rejoices that you want to mature in faith by living the Sacrament of Matrimony.

All couples are required to begin Marriage preparation by contacting the Parish Office at least 6 months prior to the anticipated wedding day. 

Pope John Paul II wrote: 
“More than ever necessary in our times is preparation of young people for marriage and family life.  In some countries it is still the families themselves that, according to ancient customs, ensure the passing on to young people of the values concerning married and family life, and they do this through a gradual process of education or initiation.  But the changes that have taken place within almost all modern societies demand that not only the family but also society and the church should be involved in the effort of properly preparing young people for their future responsibilities.”
Familiaris Consortio 66 

An extensive account of the teaching of the Catholic Church on the Sacrament of Marriage is given in the Catechism of the Catholic Church, 1601-1666

Also visit this excellent site from the United States Conference of Catholic Bishops: http://foryourmarriage.org/