They will begin to branch on their own as they mature. If it gets too tall (leggy), you can pinch off the growing tip and that will encourage branching. I just put a cane stake (the length according to the plant's height) next to a leggy, top-heavy plant, and wire the plant to the stake. That supports it well.
By the way, would you please go to your profile, click on "Update", and enter (at least) your location? It is always helpful to know where you live when asking about plants.
