I just use a large kitchen knife to cut mine down. Just cut with a sawing motion back and forth. Cover heavily with mulch and cover that with a tarp. That's it. You might not have to mulch yours depending on the species.

You might not have to cut it at all. You're in a milder zone than I am and, with my basjoos, I just cut the leaves off, and wrapped and covered them. They all came back, and they have a head start, because they start growing from the top of the stem that was left from last year. My biggest one was 4½ feet.