I have used this method with a little variation and have had 100% success rate. I wait until a week into flowering and find the females and nip my clones off the lower branches with a pair of scissors I wipe down with rubbing alcohol to sterilize them. I nip the excess leaves off and cut the main branch shorter at a 45 degree angle. I then dip it in water and make 4 light scores with a razor blade cutting the green skin layer, dip in rooting hormone from wal-mart. I then place the clone in a red party cup filled with tap water but i use a piece of saran wrap to cover the top and cut a slit to stick the clone through which also supports the clone. I change the water about every 2 days and have them sitting in the corner of my veg room. After about 7-9 days roots will start to appear which I then stick it into a jiffy cube and about 2-3 days later I transplant into my growing medium.