To use Message Templates simply click the left navigation icon to open the feature drawer.
There you will be able to add and manage your Message Templates. Click the Plus Button to add a new template. You can edit/delete any existing templates using the Pencil or Trash can icons.
When adding or editing a Message Template you'll be able to give it an internal name, "Follow Up" in the example below, and then the message that will go out to your contacts. You'll also have the option to use the Personalization Button to add personalization by clicking and selecting.
Once you've added your Message Template, it's time to use it to send out texts in your texting workflow. Open a Messages conversation and you'll see the "Message Templates" icon on the bottom.
Click the "Message Templates" icon to dropdown your saved templates and select one to use. The template will automatically populate in the text field above.
You'll notice the Field Merge Tag using the contacts first name will pull that into the message dynamically. From there just click the green "Send" button and off your message goes!