How can I keep from getting bacteria vaginosis?

Good question. Bv may happen without a known reason. However, things you can do--after being treated and clered of bv----be in a monogamous relationship. Next, consider using condoms for a while. If you are experimenting with sexual practices/acts/toys, anal intercourse, etc, perhaps you want to stop for a while and see what happens. Practice good personal hygiene. Consider no underwear or cotton undies.