The recommended way of installation of AIRe Link is through Foresight (Realwear Cloud). This will ensure that any future updates will be automatically distributed to all your RealWear devices.
Check this video to get more information about Foresight.
After you get enrolled in Foresight you can just click on your device, select Applications and then Install next to AIRe Link Client.
Another option is to use RW Explorer. This way you will have to handle app updates by yourself. Please ask us to provide current version of application package.