You may customize how any emails you send out to candidates are displayed.   You can include your logo, how your company name appears, and your signature.

These will appear on any official or automated emails you send out.

Navigate to Administration - Customize Email Branding.  

To change any specific field, select the pencil/edit icon next to the section you wish to edit.   In the text fields for your name and signature, enter whatever you wish to appear in these sections.

For your company logo, when  you select the pencil/edit icon, you will be prompted to upload a file from  your computer.