In case you want to exclude any page or url from displaying the notification, you mention the url in the display url box and switch on the exclude option.
You can use wild card like ' / ' to exclude multiple pages from displaying the notifications.
Please do not forget to click on Run on All Pages option and also the Add button once done.
In case you want the notifications to be displayed on a sub domain for example www.blog.myblog.com, you need to switch on this option after you mentioned the sub domain URL in the display url box.
Please do not forget to click on the Add button once done.
When you want to display the notifications on all the pages of your website, all you have to do is switch on this option.