There is currently no "good" way of backing up your data implemented in the application itself. This mean that you will be responsible for backing up your data.
It is planned to add a "real" backup feature similar to applications like homeassistant where a snapshot can be downloaded and restored trough the web interface.
When developing a new backup strategy, make sure to also test the restore process!
Please use any standard way of backing up your database. For most systems this can be achieved by using a dump command that will create an SQL file with all the required data.
Please refer to your Database System documentation.
I personally use a little script that I have created to automatically pull SQL dumps from a postgresql database. It is neither well tested nor documented so use at your own risk. I would recommend using it only as a starting place for your own backup strategy.
The only Data this application stores apart from the database are the media files (e.g. images) used in your recipes.
They can be found in the mediafiles mounted directory (depending on your installation).
To create a backup of those files simply copy them elsewhere. Do it the other way around for restoring.
The filenames consist of
<random uuid4>_<recipe_id>. In case you screw up really badly this can help restore data.