There are two ways of creating a group booking.

1) Choose the beds you wan to create a booking on, right click on them and click Create reservation:

Choose Group booking in Basic information section.

An extra field will appear in this section: Group Owner Name. Please note that if you don't fill it inn, the system will save a reservation as Individual

2) The second option is by using New Reservation button which you can find in two places:

The difference is that in this option you need to choose the check-in and the check-out dates:

And also you need to add the rooms. Click on Add Room Type button in order to do it:

You will see a new window where you can choose the room types you want to create the reservation for:

How I can see all my group bookings made for a selected period?

In Reservation View / BookingTypes filter uncheck Individual box and leave only Group box checked. Choose the dates you are interested in and click Go. The system will show you all your group bookings for the dates you need.