Activate the mana-producing creature by tapping it, adding at least 2.
Activate Yenna by paying 2 and tapping it, creating a token copy of Second Wind attached to the mana-producing creature, then untapping Yenna and causing you to scry 2.
Activate the Second Wind token's second ability by tapping it, untapping the mana-producing creature.
Activate Faith Healer by sacrificing the Second Wind token.