To customize the default email messages CareerPlug provides, follow these steps: 

Go to your Account > Manage Hiring Process > Message Templates. You will need to select which set of templates you want to view from the drop-down menu at the top right by choosing either general templates (which aren't currently associated with a hiring workflow) or the templates that are included in your workflow you're using. 

Dropdown for selecting message template types

If you want to make small changes to the default message template, you can instead click the Edit link to the right of the default message template. This will create a copy of the message for you to edit. Make the desired changes to the email, especially changing the name of the email, and click Update Message Template.
Updating a message template

Note: We recommend editing a copy of an existing message template rather than creating a new one. For example, if you would like to edit a message template with links, like the assessment invite, it is best to edit a copy of the default message template so you have the code there that sends the correct link to the applicant.

However, if you decide you want to create an entirely new message template, click the Create New Message Template button. Select a template category and type and click the Create Message Template button. 

Button to add a new message template

Give the template a name, type the subject line and body of the email, and then click the Create Message Template button at the bottom of the page.

You can always go back to using the default message template provided by CareerPlug by deactivating your new template and activating the CareerPlug template. Clicking the "Inactive" text to the right of the template name will make it an Active template, and vice versa.