Public Sub MyMacro()
    MsgBox "MyMacro."
End Sub

Public Sub CreateCommandBar()
    Dim cb As Office.CommandBar
    Dim cbButton As Office.CommandBarButton
    
    Set cb = Application.CommandBars.Add( _
      Name:="MyCommandBar", _
      Position:=msoBarTop, _
      MenuBar:=False, _
      Temporary:=True)
    
    Set cbButton = cb.Controls.Add( _
      Type:=msoControlButton, _
      Temporary:=True)
    
    With cbButton
        .Caption = "&Button1"
        .FaceId =  59 
        .Style = msoButtonIcon
        .OnAction = "MyMacro"
    End With
    
    cb.Visible = True
    
    Set cbButton = Nothing
    Set cb = Nothing
End Sub