Vote-by-mail ballots are mailed no sooner than 21 days and no later than 14 days before election day.
If you have not received your ballot you will need to call or visit the Davis County Clerk's office:
Davis County Admin Building
61 South Main Street, Room #104
Farmington, UT 84025
801-451-3508
http://www.davisvotes.com/
If it's sooner than a week before the election you will need to go to a voting center on Election Day in order to submit your vote.