I like the cloning method I read in High Times a while back. Dirt simple. You just need long stem cuts of six to nine inches, some soil and big beer cups. You trim all the leaves off the bottom six to nine inches, so it looks like a long stick with some leaves at the top. Kind of a palm tree. The key it to bury as much of the stem in the plastic beer cup with soil as is possible. If it doesn't all fit, twirl it at the bottom to get it all in there. Fill it in with dirt and water it good. The extra stem in the soil gives way more potential places to start roots and the stem also is used to keep the plant alive until the root takes. Now just set it under some fluorescent until it needs to be re-potted. This guy says you don't even need to put holes in the bottom of the cup, but I like the holes, so you know when you watered enough. You don't need any dome. You don't need any rooting formula. You don't need anything extra. Personally, I like to cut them the night before and sit them in a cup of water overnight, just to get them fully hydrated.