The Push notifications Add-on uses a 3rd party plugin, “Perfecty Push” to do the pushes and management
All the add-on does is trigger jobs to be pushed and provide the temple for the message
So this means the main setting are done in the Perfecty Push Plugin settings
we recommend you change these settings
make the sign generic if you plan to push blog posts as well or just jobs if not
Set the icon to your logo
Do not tick this unless you are pushing blog posts as well
You can adjust the rest, but these seem to eh main items to change.