It will die before Prepared Measures's triggered ability gets a chance to become attached to anything. As an alternative, I will suggest changing Careful Plans to "As this enters, name a card. // When a card with the chosen name enters the battlefield, transform this and attach it to that permanent."

(As it is, it will still die (and fail to become attached) if that permanent is not a creature, or if it has protection from enchantments, etc. You might change it to "when a creature with the chosen name..." in which case tokens will also count but non-creature permanents will not count; alternatively, you might change Prepared Measures to "enchant permanent" instead of "enchant creature" so that it will also work with Vehicles, lands that will later become creatures, etc. What you will change it to, depends on what you intend the card to do; as it is now, it will not work.)

Ok, fixed the rules error and changed the card to make it better.