The title is a clever pun on "Peeping Tom." Get it? "Tom", "Tie". They sound alike, but they're different, and yet a Peeping Tom is as unwelcome as your necktie peeking out from underneath the back of your collar.
You'll laugh when you're older.
It's a common problem with an easy fix. (Peeping collars, not Peeping Toms.) When you're ready to put your tie on, flip up your collar, button the top button, put in your collar stays, get the knot how you want it, and cinch it down as usual. Take a close look in the mirror and move the tie-loop up or down so that its top edge is just below the line where your collar folds. Reach around behind your neck, find the collar-fold line, and flip it down over the tie-loop in one motion. Flip the rest of the collar down, moving toward the throat.
Once the collar is in place, reach over your shoulder and stick your finger up underneath your collar. Your necktie should feel at least a quarter of an inch away from the lip of the collar.
Alternate solution: If you have a significant other or roommate who's awake when you're dressing, ask him/her to visually confirm the lack of tie-peeping.