How to text a contact?
To send a text message.
1. Open the Bigin app on your Mac.
2. Navigate to the Contacts 
module.
3. Select the desired contact record.
4. Click the Message 
icon that can be found in the middle of the screen.
Clicking the icon will open the Messages app on your Mac.
5. Type your message in the text box.
6. Hit "Enter" to send.