Summarize this article:

Many betta like to hear their person's voice. You may notice that your betta swims more actively when you talk to the tank. You can also move your finger around on the glass of the tank, or wiggle it at the surface of the water. He will try to jump toward it. Just be careful not to let him jump out of the tank. Betta fish are curious fish, and they like to play! He or she might follow you around the room when you walk around too. Having different decorations that you switch out at different times give your betta more of a variety of things to look at, and will keep his life enriched. If it is female, it MAY like the company of two or three other female betta fish. It is recommended to have more than two so they won't fight constantly if they are aggressive to one another. This is called a “female betta sorority tank.” Be prepared, however, to keep them in separate tanks if they do not get along. Male bettas most definitely CANNOT live with other male bettas. They will attack each other, which is why bettas are nicknamed “Siamese fighting fish.” A male betta can be in a tank with a female betta for breeding purposes, but you should leave this to professional aquarium breeders, or when you get more experienced with fish-keeping. Again, some betta, male or female, will never get along with others in the tank. Suggested possible tank mates for betta are apple snails, ghost shrimp, red cherry shrimp, African dwarf frogs, cory catfish, and neon tetras. If you do introduce other fish or animals to the tank, you’ll need to keep a careful eye on them. Signs include damaged fins or bodies in the other fish or water animals. You may not always see the betta attacking, but keeping a careful eye on the health of the other fish or animals in the tank is necessary. Do they look hurt? Are any of them hiding constantly? These could be signs that the betta is being aggressive toward them, and you should separate the betta for the well-being of your other fish or water animals in the tank. If you do not have a tank divider or a separate tank ready, then try adding more decorations to provide hiding places for the victims and ease for the aggressor. Treat the hurt fish first. Make sure to avoid colorful, aggressive and fish with long fins such as guppies as tank mates. Also, while neon tetras are usually okay, some other types of tetra are “fin nippers” (such as serpae tetras) so be sure to research what type you’re thinking of getting if you want to get tetras as company for your betta.

Summary:
Talk to your Betta. Move around his decorations or buy him new ones. Decide if you should introduce another betta fish for your betta. Carefully bring in some "company" to pal with the betta fish. Watch for signs of not getting along.