Super Mario 64 DS Tips

Catch the red coins you missed.
To do this, you need to do the following things:
Beat the first two Bowsers.
Get Wario.
Drain the moat.
Hit the ? button in the flying cap hidden level.

Use Wario to break the black boxes where the water used to be, get inside the opening, you will be in a hidden level. Slide down catching all the red coins you can (there are only 4 in that part) if you miss one, don't worry! keep going ahead until you find the Mario Cap, once you're Mario, go back to where the first 4 red coins are, hit the ? block, and inflate yourself to the red coins. If you want the first 2 at the top, you will have to stop at a ledge where there is another ? block, hit it, and float up to the first 2 coins.