Take softwood cuttings in June or July. Use lateral growths, i.e. ones that have grown sideways from a main upright stem. Choose material that is at least 6 inches long, take a heel cutting, trim off stringy bits at the base using a very sharp knife such as a Stanley knife. remove the leaves from the bottom third, and you can also remove the very soft bit at the top. Dip the base in hormone rooting compound and insert it in a compost / sharp sand or compost / vermiculite mix, compress the mix lightly to remove air pockets, water it and cover with a freezer bag. Keep out of direct sunlight. the cuttings should root within eight weeks.