NOLA.com offers some advice for people who find themselves living in other people's homes during Gustav. It takes some work to be a good house guest in times of emergency. Here is some advice from those who lived through Katrina:
Pre-approve animal guests. Find out in advance if your potential host will welcome your pets. Determine compatibility issues regarding their pets as well as your hosts. If you are allowed to bring your pets, keep them properly groomed and supplied with fresh food and water and don't let them roam the house unless your host insists. Be sure to clean and dispose of waste properly.
Practice good housekeeping. Remember that you're not a guest in a hotel. Not only should you pick up after yourself, you may even offer to help keep the entire household neat and tidy.
Step up to the plate for chores. Offer to perform various handyman tasks around the house (such as mowing the lawn, trimming trees or other yard work) or participate in big projects already under way. Don't forget indoor chores as well, such as dishes and laundry.
Play personal shopper and chef. Consider buying some groceries or doing the family shopping on occasion. If you can cook, offer to do this to take some of the burden off your hosts.
Babysit for kids and pets. This helps your hosts save money and provides them with some free time away from home.
Modify your morning schedule as appropriate. Let your hosts get in the bathroom first, allowing them to finish their daily routine before you begin yours.
Keep an ear to the ground. Be aware of upcoming events -- such as a planned vacation or incoming guests -- that may be mentioned by your hosts. For instance, if they tell you that relatives are arriving soon, this may be a hint that they are pressed for space.