You control a permanent that can tap to produce at least ({U} magic symbol) .
Steps
Activate the mana-producing permanent by tapping it, adding ({U} magic symbol) .
Activate Fatestitcher's unearth ability by paying ({U} magic symbol) , returning it from your graveyard to the battlefield and giving it haste until end of turn.
Activate Fatestitcher by tapping it, untapping the mana-producing permanent.