To export your itinerary, you first need to integrate your account with Google. Refer here to see how to do this.
Once you have finalized all the details of the trip, click the "Add to Calendar" button on the lower left-hand side of the itinerary. It should appear on your calendar within 3 minutes. If you need to change your itinerary, go ahead and do so on TRAVO's trip planning software. Then re-add your itinerary to your calendar. TRAVO will automatically delete your previous export and update your calendar with your new itinerary.