Complete one of the indicated tasks to unlock a star at the title screen.

Successfully complete the game.
Successfully complete all normal levels.
Collect all 207 Star Coins in Worlds 1 through 8.
Complete World 9 with all 24 Star Coins.
Complete all levels with all alternate paths (all Warp Cannons and Mushroom Houses used).
Additionally, successfully complete all levels without unlocking the Super Guide Block (do not die eight times) to unlock sparkling stars.