Read or download the Missionary Preparation Student Manual. This is the 2005 version.
Also, here is the Missionary Preparation Teachers’ Manual. This one is from 2014, and the chapter titles are different than the student manual. I’m not sure why the difference–I suspect it may be that the Church is not publishing a student manual anymore–the Preach My Gospel manual may now serve as the student manual for the class.
Introduction to the Mission Prep Student Manual
President Gordon B. Hinckley taught that “themission of the Church is to save souls. It is toteach the gospel to those who are willing to listenwherever they may be. . . . There is no greater work.There is no more important work. There is no morecompelling work than this which the God of heavenhas given us responsibility for accomplishing” (“Missionary Service,” First Worldwide LeadershipTraining Meeting, Jan. 2003, 21).
You are preparing to accept a God-given responsibility. The work you will do as a missionary will be in fulfillment of the Savior’s commission to “teach all nations” (Matthew 28:19). Your purpose as a missionary is to “invite others to come unto Christ by helping them receive the restored gospel through faith in Jesus Christ and His Atonement, repentance, baptism, receiving the gift of the Holy Ghost, and enduring to the end” (Preach My Gospel [2004], 1).
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An additional resource is the guide to missionary service, Preach My Gospel, used by missionaries around the world. The Missionary Preparation Student Manual corresponds with Preach My Gospel in principle and philosophy. It has been carefully written to prepare you with an understanding of the doctrines and principles upon which the missionary program and Preach My Gospel are centered. Using this student manual and participating in a missionary preparation course will help prepare you for full-time missionary service, where Preach My Gospel is the core training resource.