Once you lose the Internet from your existing ISP then switch over and plug in your NOW Hub Router.
Wait for the three green lights to illuminate on the front of the NOW Hub and you are good to go.
Just be aware it could take a couple of hours after losing the Internet from previous ISP to actually go live and it could take up to midnight.
I have done three NOW Broadband switch overs and for me the longest took around about 8"pm.
If on Sky, plug in your NOW Hub Router straight away or if there is no previous Internet running at your home then again plug in and power up the NOW Router and just wait.
If that's the case just plug in the NOW Hub Router and wait for the three lights to permanently remain green on the front of the Router.
Once all three green lights are permanently on your Internet has gone live.
It still can take up to Midnight.
Once you have gone live your online account under the Broadband & Calls > Orders & Appointments should also confirm the activation has been completed but this may take a couple of hours to update your account status.