Geraniums are one of the simplest flowers to propagate. Today I took several cuttings from 3 geraniums I am overwintering so I will have enough to plant out this spring. I take off about 2/3 of the mother plant which still has leaves of mass to grow into healthy, beautiful plants. The cuttings are then stripped of all but 2-3 small leaves, dipped into rooting hormone, and placed into damp medium. I find that the roots will be stronger with this method. Another method of propagating geraniums is to place cuttings into a vase of water. No matter which method you choose, you will be blessed with an abundance of beautiful flowers all summer long.
Don't forget that in the fall, you can take cuttings from those you planted out this spring to save over the winter to repeat the process next year.