When you cut the head, you will need to create a way to attach your leader. You can buy a pack of Rio Braided Loops and add them to the head. We suggest the 3-6 weight loops since they fit best on the relatively thin line diameter of these heads.
If you are comfortable tying an Albright Knot, you can add a butt section of monofilament and then put a loop in it. We generally do not suggest a nail knot since they often pull off the head when placed under heavy pressure.