Print out a photo of yourself with a double chin, and hang it from your car. Let it serve as a reminder to push the back of your head against the headrest when you drive, strengthening the muscles behind your neck.
Regularly perform the following exercise: Stand against the wall with your ankles, butt, shoulders, elbow and head all in contact w/ the wall. Slowly raise your elbows up and down while maintaining contact.
Wait one month, then take the photo again and fill out the survey again. Hopefully, life will be better.