So, its not very clear. On your computer (I have a macbook pro) there is an icon for the App Store. Look for a blue circle with a white A made from a brush, a pencil, and a ruler, inside it. Open the App Store by clicking on it. Search Evernote. Once you find it, you should be able to choose it and install it on your device. (Unless you are using the Basic service and already have it on two devices.) Once you install it, open it and sign in to your account. The app should appear in your application folder; it also put an Evergreen icon in the top tool (?) bar of my computer, as well as in my dock. Hope that helps. Evernote could definitely explain this better and make it easier to add a device.