Pres Zundel has asked young men/women to review the Interview Questions for Prospective Missionaries (from the church handbook), as well as prepare to discuss these topics:
Preach My Gospel - Lesson 3 - The Gospel of Jesus Christ - section "Repentance through the Atonement of Jesus Christ"
Preach My Gospel - Lesson 4 - The Commandments - starting with section "Obedience" and continuing through remaining ones
Gospel Principles - Chapter 31 - Honesty - entire chapter
For young men: if you're also being interviewed to receive the Melchizedek priesthood (to be ordained an elder), additionally review & ponder Doctrine & Covenants 84:33-41.
When meeting for an interview, please follow the dress/appearance standards outlined in the missionary application (another resource is Callings and Training page on the church website per this section: Missionary > Young Teaching Missionaries > Dress and Appearance Standards).
Info for YM/YW preparing to serve a mission, including the Mission Applicants Process/Prep folder, contains helpful info for those currently making preparations (click below to open in new window).