The matrimonial covenant, by which a man and a woman establish between themselves a partnership of the whole of life, is by its nature ordered toward the good of the spouses and the procreation and education of offspring; this covenant between baptized persons has been raised by Christ the Lord to the dignity of a sacrament.
Dynamic Catholic, a non-profit organization, has put together a fantastic marriage preparation program. Available free online here.
Check out their wedding planning book too. With everything in one place, the ride from “He proposed!” to “We’re married!” will be smooth sailing. Both are phenomenal resources for newly engaged couples!