Add a mobile phone number to receive SMS notification. Go to contacts panel ("Account" -> "Manage Contacts" -> "Add a Phone Number"), enter a phone number in international format you wish to add.
To verify phone number two options are available:
- Short Code - Short digit code will be sent to the phone number, you will have to prompt it in Accounts panel. Good for simple phones, of if the phone is physically accessible
- Link - A verification link will be sent to a phone number. Good for smart-phones or if you add phone number of another person.