How do you complete a galaxy in Super Mario Galaxy?

Answer 1

getall the stars and the boss if does not work use YouTube

The Main Galaxy that have 3 normal mission have one hidden star, and 2 comet stars for a total of 6 star, The 15 Main Galaxy only 2 of them got 2 hidden star instead of 1 hidden star because of the green star hidden so two main galaxy would have a total of 7 star instead, a hidden yellow star appears as a yellow "?" on the mission it is hidden in, The hidden green star appears as a green "?" on the mission it is hidden in. However the "?" will only appear if the currently available star are collected. The first comet can be one of this type Fast foe comet yellow, Cosmic comet blue, speedy comet red, daredevil comet grey, the second type of Comet is the Purple coin Comet is only unlocked when you get the grand star in the bed room Dome plus your total star must be 60 star, and obtain the 7 grand star and let the credit scroll to save the game. If you get 60 star before rescuing the 6 grand star you can save the 7 grand star before the 6th grand star, however the 7 grand star does not give more Power to the observatory to unlocked gate way galaxy and the Garden Dome.

Answer 2

keep getting stars! and your friends will complete it themselves

Answer 3

First get 120 stars and then the 120 green stars, for a total of 240 stars