If you are going to drink during Mardi Gras, take it easy and slow. Most important, it's easy to get caught up in all the excitement and forget to eat. If you want to make it through Mardi Gras, solid food is a necessity. Of course, New Orleans is world famous for its food and is part of a complete New Orleans experience. Toilets Clean bathrooms are a difficult thing to find during Mardi Gras.
Every business closes their facilities to everyone but paying customers.
If your hotel is far from the action, take care of the more important business before you hit the streets. However, they have long lines and can be quite an experience. This is a fine way to end up in central lock up and people who are arrested during carnival sit in jail until the courts re-open after Fat Tuesday. Besides, it's not polite. Listen to your body.