Ofcourse I could fly first class on an airline that provide onboard showers. Since I lack the funds that is not an option for me. 
The scenario is as follows. Your plane leaves in the evening. During the day you just enjoy the city, but it appears to be just a bit more sunny then you expected. Since you already checked out from your hotel you are not able to take a shower before heading for the airport. At the airport the showers are unavailable due to technicalities. You then buy some tax free after shave to freshen up. You then have a 12 hour flight, after which  you have to transfer between terminals in a packed bus while it is 30 degrees Celsius. When you board your connecting flight you realize that a cocktail of 24 hours of dried sweat and 12 hours dried aftershave just not add up and that the persons sitting next to you on the connecting flight are going to have a very uncomfortable flight. 

Is there anything you can do to prevent this awkward situation?