Samba is installed and configured, but configured for guest.

[handlenyc]

Hello,
In the following Instructables, I read "Samba is installed and configured, but configured for guest. You'll want to lock that down if you want it to be secured."
https://www.instructables.com/Dynaframe-a-Feature-Rich-Photo-Video-Frame/

I just saw this link in the Instructables, but there does not seem to be any information there anymore. https://everyday-tech.com/samba-share-on-your-raspberry-pi/

Could you point me to instructions on how to "lock this down" and/or create my own users to access the FRAME folder for images and videos?

Thank you