I save the small crumbles and dust that are in the bottom of the chickens' bowls in a separate container. Then I use this for "chickie snack." I wet it down as
@Ascholten does, and put any kitchen/garden scraps on top. Chickie snack is usually in the late afternoon, so I guess I could say I feed them twice a day, as I put out fresh dry food every morning. Very little of their feed gets wasted.
I use whey if I have it (leftover from making yogurt), and sometimes kombucha with extra scobys I have.
The way prices are going on everything, I may save my coffee grounds in a separate compost container and give the chickens everything else, unless there's something icky that they shouldn't have. I don't like avocados (shame on me) and I'll be saving citrus peels for kindling now that I've heard about how great they are.
We throw out bread more than I'd like to see. I'm GF, and there are extra buns or heels left over that DH won't and I can't eat. I haven't been giving them to the chickens except about 1x a month, as a really special treat, and then 1 heel torn into bits for the 7 of them.