Inside your Quest library, look under "Unknown Sources." Launch BMBF. Accept any file permissions it asks for.
Inside BMBF (via the web browser interface it host), navigate to the "Browser" tab. Install the core mods (SongCore, Custom Types, etc.) available in the bmbf.dev.stable repository. bmbf.dev.stable
If you have ever searched for how to mod Beat Saber on a standalone Meta Quest headset (Quest, Quest 2, or Quest 3), you have almost certainly encountered the cryptic code: . Inside your Quest library, look under "Unknown Sources
This is the most important rule of BMBF: Install the core mods (SongCore, Custom Types, etc
However, if you own a Quest 3 or keep your device auto-updated, you will likely find that bmbf.dev.stable leads to a dead end or an incompatible download. In that case, your search should pivot to modern alternatives like MBF.