Option one is simple. I wear either a O2 rain jacket or shower pass for the top. A skull cap and a bacalava on colder days. The bottom is a little bit different. I use a Rain Leg for the upper half, a gaitor for the calves and fenders to help keep my shoe dry along with the gaitors.

Otion two: Call in sick on those days where it is pouring and build a nice lovely warm fire in my fireplace at home.