Select the desired Sender ID, this is the mobile number or Name that the recipients will see on the SMS.
If you have permission to send SMS messages on behalf of another user, you can select them in the Sender drop down.
If the SMS message is in regards to a listing, select the listing and the SMS message will show against that listing as a communication.
Enter the SMS message into the message field.
Click "Preview" to see how many SMS credits you will use.
Click "Send SMS".