You can add recipients to a Flight (even if they aren't in Salesforce) by uploading a CSV. Just follow these steps:
1. Start a Flight.
2. Select the CSV Upload tab and click the Upload a CSV button.
Important: Your CSV must include one column named Email that includes the recipient email address. In addition, all column names must be capitalized (e.g. Name, Email, etc.).
3. After selecting the CSV file, you can confirm the file name, as well as the number of email addresses and merge tags imported. Press the red Continue button.
4. Choose a Flight Plan.
5. Set the start date and confirm steps and recipients. Press the Start Flights button.
Note: If adding recipients that aren't in Salesforce, keep in mind that any steps which include templates, call scripts, etc. with Salesforce-centric information will have to be completed manually. If sending a Flight to a large number of non-Salesforce recipients, it may be best to create a new Flight Plan that utilizes non-Salesforce information.