Initially, link your Roku device to your wireless network (WiFi) and once done, The Activation code will pop up on your screen. After you note down the activation code, type Roku.com/link in your mobile or PC browser. Now in the space provided, type in the activation code without any errors. Moving Further, follow the instructions on the website to sign up or login to your Roku account. Do not worry! The payment information asked for does not allow any charges to your account. Hence, it is purely for future purchases, if any. Roku activation is in the can.