For Skype video calling, you will need:
Once you have a Skype account, navigate to your PukkaTeam settings (via the top right menu under your profile picture), add your Skype username and save and you're ready to go.
Now when you hover over a teammates snapshot, there will be a button for you to call using Skype.
The first time you click to call someone you may be prompted with a popup asking which app you want to launch. Select 'Skype' and click 'Launch Application' (or equivalent depending on your browser) and this will open Skype and begin the call. You can then easily upgrade the call to add video through Skype as you normally would.