Most days on a tour, I spend five or ten minutes each evening doing hand laundering. And if I am lucky and my timing is good, I use a washing machine every five or seven days. This system allows me to minimize the amount of stuff I have.
I carry few non-cycling clothes. Usually I have two shirts, one pair of long pants, one pair of short pants, two pairs of socks, two or three pairs of underwear. A shirt that I wear in the evenings remains "reasonably" fresh for four or five days. As a trip draws to a close, I stop doing laundry, and try to return home with my panniers filled with stinky stuff!
As for cycling clothes, I carry one cycling jersey, one pair of padded shorts, a few pairs of cycling socks, and that's about it. This is the main focus of my daily laundering ritual. Plus I have items for cold and wet weather, a belt, a pair of lightweight shoes, a pair of sandals, and that's about it for clothes.