Recommended way to create 4 trips for the 4 family members who travel together

Hello,

What is the recommended way to create 4 trips on my Global Mobile pass for the 4 family members who travel together?

Do I create an empty trip and then make 3 copies and link each empty trip to a person?

After that, do I search for journeys and add each journey to all 4 trips at the same time? So, in this way, I start with 4 empty trips and then keep on adding journeys? 

Our holiday includes 15 days of train rides over a month.
So, do I create one trip and add all the 15 different journeys to the trip?

Then, how do I add special reservations like the Glacier Express to the mobile pass?