improving cadence

So I think I'm pretty much a masher. My computer normally says high 70's for cadence. I think I would like to improve on cadence over the winter if I will benefit from it. I def have endurance so that is not an issue.  My question is will I loose some power first when attempting to do this. Say I ride 4 times a week for atleast a hour. How often do I practice my cadence drills? All 4 times? Do I do the cadence drills for only part of my rides? I know my next question is vague, but when could I expect results? What are your experiences like?