Mario & Sonic at Vancouver Olympics

To unlock a characters' costumesYou need to uses that character and win 5 golds or/and 1st medals in any Olympic/Dream Events.(In single, co-op, and festival mode)

To unlock the emblems in the game, achieve the following accomplishments.

You can unlock special costumes for Miis while playing. Mii Character Costumes not only change your Miis appearance, but they also adjust the Mii's Statlines to match the character. Playable Character Costumes are unlocked simply by playing a lot of different events with the respective characters. However, there are some special costumes that can only be unlocked via special means.

After a few hours of play time or completing a Festival Mode, you'll receive a note saying there may be a secret shop in the shopping district. Go there, and stop the camera between the far left and middle buildings -- aim the pointer at the shop down the alleyway between the two to reach the Secret Shop.

To unlock the Dream Events, complete the following tasks. Note there is more than one way to unlock every Dream Event. Unlocking an event will make it accessible in single-event mode as well.

A while into the game, you will get mail stating that certain characters are in certain dream events cheering you on. Two of those characters will give you costumes if you spot them.