Communicating the Small Stuff

OK. I teach and coach about relationships. Everybody knows that communication is one of the pillars of a healthy relationship. In relationship communication I have learned to communicate the big stuff - like: "You are acting like a jerk" or "when you don't talk to me, I feel scared about our relationship and don't know what's going on," etc.

But how do I let you know things like, "You have dandruff "or "you dripped on the bathroom floor or messed up the sheets?" Those things are so personal and seem so hard to communicate and so petty to boot. I just want to let them go. But then I end up resentful. You know, little thing on top of little thing on top of clean up after you and say nothing, on top of little thing and I'm ready to walk right out the door.

I was in a great relationship for 31 years and I still haven't learned the best way to do it.

Any ideas on relationship communication on those really personal and bugging things?