Too many youth have that terribly wrong perception. Preparation for a mission--most essentially, the temple--is a lifelong pursuit. It starts at childhood, not the year (or month for most women) before entering the temple.
Two Primary songs emphasize this point:
While I am in my early years,
I'll prepare most carefully,
So I can marry in God's temple for eternity.
("Families Can Be Together Forever," Children's Songbook, p. 188)
I love to see the temple.
I'm going there someday . . .
I'll prepare myself while I am young;
This is my sacred duty.
("I Love to See the Temple," Children's Songbook, p. 95)
"Someday" comes sooner than you think. And it's hard to break years of bad habits and repent of years of sins in just a few months.
"For behold, this life is the time for men to prepare to meet God," Amulek warned us (Alma 34:32). We prepare to meet God by receiving and keeping sacred temple covenants. And we prepare for that right now. The only change we should have to make upon receiving our endowments is the underclothing we wear--not our language, not our clothes, not any Church standards we should already be keeping. The commandments apply to all members, whether or not they have gone through the temple.
If we already are endowed, we still need to prepare every time we go to the temple or renew our recommend, and we are to remember and honor our covenants every day. The temple isn't a destination we arrive at but a vital pit stop we go to continually for spiritual fuel and direction on the journey back to our Heavenly Father.
As a parent, the moment a baby is born, it is our responsibility to set that child on the right track to the temple. We should be examples to our children of attending the temple regularly, keeping our covenants, treating our garments respectfully, and having high standards as a family, especially of modesty.
President Kimball advised, “It would be a fine thing if … parents would have in every bedroom in their house a picture of the temple so [their children] from the time [they are] infant[s] could look at the picture every day [until] it becomes a part of [their lives]. When [they reach] the age that [they need] to make [the] very important decision [concerning going to the temple], it will have already been made” (The Teachings of Spencer W. Kimball, ed. Edward L. Kimball, 1982, 301).
Challenge: Prepare yourself and your children to make and keep sacred covenants.