Go to Mobile Marketing > SMS Broadcast
You will now be able to change below settings.
Put in your message to send.
Enter the numbers you want to send the messages to.
Enter in a valid originator that the message will appear from.
Send Date and Time
You can send the message immediately or you can schedule a date and time to send it.
Expiry Date and Time
Set an expiry date.
Now you can send a single test message with the settings above to a mobile number (modal popup), send the broadcast message or clear all the above settings to start again.