Select Dynamically allocated and click “Next”.

Select the location of the virtual hard disk, name it, choose its size. In this case these options can be left as is. Then click “Create”.

Once you completed this wizard you should end up on the main screen of VirtualBox. Before starting the virtual machine for the first time, I always adjusts some options. To do so, right click on the virtual machine that we just created and select “Configuration”…

In this new window, click “Display” in the left column.

Adjust the video memory to 128MB and enable 3D acceleration. Then click “Storage” in the left column.