Untap, upkeep, draw a card from the Bauble (I don't think you actually get an upkeep on your first turn, but either way I have the Bauble draw now), draw, Chromatic Sphere, done.
Melkor: 20
Hand: 7
Library: 37
In Play:
(U) Underground Sea
Graveyard:
RFG:
Oversoul: 20
Hand: 5
Library: 31
In Play:
(T) Thran Quarry (T: mana of any color; dies at EOT if I have no creatures)
(U) Tinder Wall (0/3 sac: RR; R, sac: 2 damage to a creature it blocks)
(U) Chromatic Sphere (1, T, sac: adds one mana of any color and I draw a card)
Graveyard: Urza's Bauble
RFG: