790 votesmontuos commented
Anonymous: On most systems, if you doubleclick the Takeout file, it will open in the default zip/unzip utility. If it doesn't, then look for some kind of zip entry in your start menu under accessories, or programs, or utilities and open the Takeout file with that.
Once it is open in the zip utility, you want to extract the file. It will be nested inside a folder structure like email@example.com\Reader\subscriptions.xml . You can either select to extract only that file, or you can extract the entire thing and then navigate to the file from the import process when you run it from the website.
Make sure you pay attention to where you extract it so you will be able to find it again for the import!