To bookmark an RSS feed, browse to the page you want to get your RSS feed from. Click on the RSS button on the right side of the address bar.
This will pop up the RSS Feed site on that particular web page. Notice the difference in the RSS icon.
Next, click the Add (+) button on the navigation bar. Type in the name of the bookmark, choose where you want to save it then click the Add button.
Now go to the bookmark you saved and you can check out the latest articles via RSS!