See our Package options here: What is the Basic Package? What is the Feedback Package? What is the Pro Package?
To add a Free Trial, simply go to "Add Course" and find the course you you want to try:
Select "Free" under Choose Your Package and then click "Try Free!":
It will then automatically be added to your account under "My Courses"
If you would like any help adding your free trial, please contact our support team at firstname.lastname@example.org