Firstly you need to add the service to the system from the Additional Services tab in the settings area, when you add the service make sure to tag the service with the Transport/Taxi category id, also make sure to set the service as schedulable (via the checkbox).
This category is used to generate a taxi/transport report that you can send to your driver who will be doing the pickups.
Note, when you add a service to a booking you can set the date and time that the service is to be carried out at, when adding a taxi/transport service, for bookings that check in and out on the same day the date of the service will automatically be set.
While for boarding bookings when adding the service you have some additional options when selecting the quantity, if you select 'Checkin Day' from the quantity drop-down list the date of the service will be set automatically, likewise for the other quantities, for numerical quantities the dates are not automatically set.
Once you have some services in the system, you can run the taxi/transport report from the Reports Quick menu in at the top of the daily overview page, or from the main reports section (graph icon in the main menu).