Variants

How this can be done?

a) Magic watch\another artifact that allows to rewind time back, but no more than 24 hours
b) Magic ability to say "it's only a dream" And it does become a dream, returning main character back to the moment when he woke up
c) Ability to live any given hour twice\thrice, then choose what timeline to keep ( that's good because while main character can choose, if he screws badly in all cases he'll still need to choose)