I have so many of these plants, time to cut them down and start fresh. You get a 8" + cutting with some colored leaves. I'll cut it and mail it in the same hour.  The procedure for getting them to root is easily researched on Youtube. I prefer to stick them in a cup of water until the white roots start to come out--watch water level for evaporation. Then transplant them to a CLEAR starter pot (keep soil moist). A clear pot lets you see the roots filling out. When you get a good amount of root visibility/crowding you are ready to transplant your cordyline to its final home.