Download the file and follow the installation instructions. Note: You will be prompted to close all browsers during installation. Once installed successfully, you can enable to add-on in your browser and set dialing code preferences. To make phone numbers appear as links, make sure to enable the "Turn number highlighting on" preference from the Click to Dial toolbar. Close the browser, restart a new browser session and log into NetSuite. Pages containing phone numbers will be highlighted/clickable and available to call from Skype.
See the Skype Click to Call FAQ for more information at: https://support.skype.com/en/faq/FA657/how-do-i-use-skype-click-to-call