The best solution to prevent further tooth damage is to have this professionally done by a dentist’s office.
They will take an impression of your teeth. This will be sent to a lab which will produce a strong but soft and resilient bite plate.
The one I had went over the bottom teeth and acted as a cushion.
It may be an initial expense but it’s worth it to prevent thousands of dollars in later repair from cracked and worn teeth.
For some people its caused by tension but for others it’s just an unconscious habit.
The best solution, regardless of cause, is continuous use of the bite plate. It’s not that difficult to get used to the soft kind. It’s only worn at night when you’re sleeping.
If you also grind your teeth during the daytime, that is most likely tension related and calls for different approaches since a soft bite plate isn’t too practical in daytime.