I'm unclear on the mechanics when paying for a spell using a land enchanted by Wild Growth or Utopia Sprawl. I announce my spell, name the target(s) if any, tap a Forest or whatever for G, and then what? Wild Growth's ability triggers mid-payment, and players have a chance to respond? Essentially, I want to know how to sequence and verbalize this correctly. And if anyone wants to enlighten me on the correct way to make it known that I'm "floating mana" that would be cool too. Thanks!