I just chuck mine in the machine with the rest of my things. Usual cold wash, spin dry. Then I hang it inside to dry.
For a longer lasting binder, keep it out of the dryer. I'd also go as far as to say keep it out of very hot sun. Always hang by the bottom, never the shoulders (same goes for any shirt like item, really).
They're pretty sturdy. There isn't much you can do wrong. They're made to be owned and washed by men, after all - we aren't known to read care labels on things! 😉