I don't have much to go on here. If your plant is outside for the summer in a pot, you can simply move it indoors before frost. If it's in the ground, you can try to dig it up and pot it, or take cuttings. Clip off the tips of the branches to create cuttings about 4 to 5 inches in length. Then, dip the cut end in rooting hormone (you can buy at garden centers) and place in a sterile potting medium such as vermiculite or seed starting mix. Then, keep them slightly moist and out of direct sun. Once they develop leaves you can pot them up. However, I must add that this is a lot of work for a plant you can buy at very inexpensive prices in the holiday season. By the time you buy the rooting hormone, the planting medium, flat to grow them in, potting soil, pots, etc, you will have spent more than it would cost to buy a number of new healthy, in-bloom plants. Cuttings are very difficult to ever get to bloom on your own because they need special treatment in dark conditions to bloom. And, for the holidays, it's already too late to take cuttings for flowers this year.