You don't want to take clones from flowering plants.
You keep a plant of the strain your are growing in a permenant vegetative state. 18-24 hours, fluorescent lighting is cheap and effective. You take clones from this plant.
Clones from flowering plants do not do well.
Also, when taking cuttings from your mother plants, i have read, that cutting off more than 25% of the plant is stressful on the plant. So cutting it back to one node would not be ideal.
I say this, but I often cut 60-70% off of my mother plants after taking clones. Just so they use less water and I don't have to mess with them for a while. I plants that are over 5 years old and have been clones of clones of clones,etc, frquently cut back and still produce.
Research the bonzai mother plant. Its real easy, that's what is done here.
You'll find your own flow of keeping mother plants and taking clones to stock your garden. There is no "right" way to do it. It just depends on your genetics, setup, etc.
The great thing about cloning is that you REALLY get to know your plant. What it wants, what training works best, etc.