procedure TForm1.Button1Click(Sender: TObject);
var
  Group: TRibbonGroup;
  TabItem: TRibbonTabItem;
  BarItem: TActionBarItem;
  BarAction: TActionClientItem;
begin
  TabItem := Ribbon1.Tabs.Add;
  TabItem.Caption := 'Tab caption';

  Group := TRibbonGroup.Create(Ribbon1);
  Group.Parent := TabItem.Page;
  Group.Caption := 'Group caption';

  BarItem := ActionManager1.ActionBars.Add;

  BarAction := BarItem.Items.Add;
  BarAction.Action := Action1;
  BarAction.Caption := 'Action 1 caption';

  BarAction := BarItem.Items.Add;
  BarAction.Action := Action2;
  BarAction.Caption := 'Action 2 caption';

  BarItem.ActionBar := Group;
end;