On SMS you can just send REGISTER to 9870807070 to sign up for the service. You will receive a reply ‘You’ve accepted the Terms of Service at http://labs.google.co.in/smschannels/termsofuse. To subscribe, reply ON channel name. eg. ON GoogleNews. For more commands reply HELP’
The website as well as SMS commands on the phone allow you to configure settings, create and subscribe to channels and even view past messages on a channel.
You need to verify your phone number while signing up with SMS Channels service from the web front end. After you sign in to the SMS Channel web front end using your Google account, Google will send you the verification code via SMS to the phone number you have entered. You’ll need to type in the verification code on our web front end to complete the sign up process. Usually it takes few minutes to receive the verification code. However, network delays may cause the verification code to be delivered at a later time.
If you haven’t received the verification code, you will need to send an email to firstname.lastname@example.org with your mobile number and a preferred time where we can call you and help you with the verification code. [source: google help]