Well, all those fancy chemical products you can spray on your suit can be fine during a con where you cant get near a washing machine, BUT that doesnt mean you should not wash your suit.
If a suit is made properly it should not break if you wash it. Turn the inside out, wash on a gently cycle (30 degree) and use some wool fabric soap.
Trust me, though chemicals will take the top of the smells for a shorter period of time, it wont last forever. Besides is very gross not to wash your suit at all. If you suit is heavy airbrushed gently washing by hand in a tub can be done too.
I would not recommend washing your head in the machine though.
I have washed Honey Bunnys body many many times and it has never broken. Never dry it in a tumbler though. When your suit is done, turn it back from inside out and brush it out (to prevent matting) and hang it to dry.