If you create a new empty dataset, the valuetable will be opened in order to insert values.
After this the propertydialog will be opened to gibe you the oportunity to change the settings (name, color,...).
Call with: Shortcut: STRG+N
Menu:
File->Add series->New (1D)
File->Add xy-data->New (2D)
File->Add data->New (3D)
Popup, that appears, if you press the right mouse button:
Add series->New (1D)
Add xy-data->New (2D)
Add data->New (3D)