There are a couple ways to create your Light account.
Creating an Account on the Device
You can create a Light account on the Light Phone II itself from the settings.
Settings > Account & Info > Light Account > Create/Log In
Follow the on screen instructions to create a new Light account. You will provide an email address as well as a password for your account. Once created you will can log into the Dashboard website and control your Light Phone II.
Creating an Account on the Dashboard Website
You can also create a Light account on the Dashboard website by clicking "create a new account" at the bottom of the login page