I can add to that, always wear, or have available in your carry on gear, clothes that are suitable for your destination (at all hours) or indeed any possible unscheduled stop overs between your point of departure and destination.
Another trick for having a spare change of clothing (only applies if you're traveling with a companion): Each of you pack you're own separate bag but also each of you also put one complete change of clothing and a personal kit (toothbrush, etc.) into the other's bag. The chances are that if the airline loses one person's bag, they won't lose both. Not foolproof but it improves your odds.