Division is the bomb. It gives you a whole bunch of new plants that are already well established at no cost. Of course they need some time to settle in but are usually much more instantly gratifying than a planting a seed. So, grab a plant, pull it apart, plant the bits, new plants, wonderful.
Of course it is not quite that simple, here is the breakdown.
Grab a plant: Plant selection is the key. Choose plants that form clumps. Plants such as artichoke, mint, thyme, oregano, rhubarb, chives and tarragon grow this way and are good candidates for division. Spring or Autumn are the best time to divide plants.
Pull it apart: Pull the plant out of the pot or gently dig it out of the soil. Tease the roots apart then use a sharp knife to cleanly cut any roots that are still holding the clumps together. It will also pay to trim back any damaged roots to a healthy node.
Plant the bits: Well this is done just how it is said. Lovingly plant the divided plants into their desired locations. Give them a good watering and keep an eye on them every day or so to see how they are going. Pot some up for your friends.
New Plants, wonderful: Yes they are, well done.