The public beta (what is more appropriate for the original poster & other non-developers) of macOS Big Sur is now officially available: https://beta.apple.com/sp/betaprogram/guide#macos Anything before this was not recommended for non-developers, people that need their computer & data to work reliably, etc. Even then, this public beta is still a beta. Things will still not be working entirely correctly (including third-party software that hasn't updated to support the new version yet [since it's not officially released yet]) even with this being a publicly-available beta (key word still being beta.) If you need things to continue to work smoothly, the official release isn't too far away & you should probably wait. Keep in mind that even official releases can have some bugs (many potentially having to do with third-party software, at that point) so getting it earlier & earlier before then just leaves you open for more & more problems (definitely shouldn't step outside of what upgrade profile you officially have like many have suggested here since you then can't get proper support if/when things happen.) Of course, I wouldn't hold off on an official release (when that happens in the next couple months), though, unless there's a known compatibility issue with something you need.

Keep in mind that the solution by Steffen_Volgmann - https://developer.apple.com/forums/thread/649715?answerId=621273022#621273022 does put you on the developer beta path instead of the public beta path. As such, these are betas not seen to be fit for the public beta program yet (let alone to be used for reliable general use that comes with the official full release) & are more likely to have bugs & other issues of varying seriousness (some potentially being quite serious [possibly even totally messing up your synced data, needing a full re-install/restore from backup, etc.]) Apple doesn't have the public beta of Big Sur currently available on purpose so keep that in mind when deciding whether or not to move forward with the developer beta profile. I'd recommend waiting for the full release this fall if you're planning on general use, but certainly wait for the public beta if you're not a developer that absolutely needs it & is prepared to deal with the issues it has (potentially then not being able to get sufficient support due to running the developer beta without an active developer plan.)