There is a quick way to copy a previous trip, with all its reservations or less, and use it for an upcoming trip for new clients.
Step 1: Locate the trip you want in your "Trips" section. To the left, you will click onto the 'Action' wheel.
Step 2: Click onto 'Copy Trip' and you will get the following as shown below. Select the details you want to copy by ticking the boxes.
You can find your new copied trip as the top entry in the trip page accessed from the dashboard. You can then click on the trip and keep working as necessary.