Mario was created by Shigeru Miyamoto as Nintendo's mascot and is an extremely well known video game character, possibly the most well known of all time. Imitating Mario's style for a Halloween event or a fancy dress party isn't that difficult and can be a great last minute choice because it's likely you'll have the items needed in the closet somewhere in the house! If not, take a quick trip to the local thrift store. Here are some suggestions and illustrations to assist your dressing up activity.
Step 1 Dress in blue overalls and a red shirt

These don't have to be in great shape, and if you don't have overalls, just wear a red shirt and blue pants/jeans.
Step 2 Add a red cap

It is helpful if you can draw or stick on a capital "M".
Step 3 Stick on a fake mustache

Use a ready-made mustache, or make one from fake fur/fluff. Another alternative is to draw one on if needed.
Step 4 Imitate Mario's physique

Perhaps add some padding around the tummy for a more round appearance.
Step 5 Add white gloves. These are trademark Mario.
Step 6 Wear comfortable brown colored shoes

Mario isn't going to be running around in expensive shoes!
Tips
- Try some Italian phrases. Copy phrases from the games if wished.
- Color the buttons on your overalls yellow if you have the time/inclination to do so. Even round yellow stickers will suffice to fix the buttons.
- For a classic look, get a blue shirt and red overalls.
- Get your friends to dress up as other Mario characters:
- For a girl: Peach
- For a guy a bit taller than you but younger than you: Luigi
- For either gender: Toad or Toadette, or Yoshi
Things You'll Need
- Overalls
- Red t-shirt or long-sleeved top
- Black mustache
- Red cap with "M" marked on it
- Comfortable shoes
- White gloves