Programmatically add a list of properties to a document type in Umbraco. In this case, add the sidebar tab and properties.

Sidebar.cs

var dt = DocumentType.GetByAlias("Test");

var sidebar = new DataTypeDefinition(1424);
var note = new DataTypeDefinition(1485);
var picker = new DataTypeDefinition(1034);
var trueFalse = new DataTypeDefinition(-49);
var textString = new DataTypeDefinition(-88);

var list = new List<Tuple<DataTypeDefinition, string, string>> {
    new Tuple<DataTypeDefinition, string, string>(trueFalse, "sidebarEnabled", "Enable Sidebar"),
    new Tuple<DataTypeDefinition, string, string>(note, "sidebarNote", "Sidebar Note"),
    new Tuple<DataTypeDefinition, string, string>(picker, "sidebarNode", "Use Sidebar From Another Page"),
    new Tuple<DataTypeDefinition, string, string>(textString, "sidebarTitle1", "Title"),
    new Tuple<DataTypeDefinition, string, string>(sidebar, "sidebar1", "Items"),
    new Tuple<DataTypeDefinition, string, string>(textString, "sidebarTitle2", "Title"),
    new Tuple<DataTypeDefinition, string, string>(sidebar, "sidebar2", "Items"),
    new Tuple<DataTypeDefinition, string, string>(textString, "sidebarTitle3", "Title"),
    new Tuple<DataTypeDefinition, string, string>(sidebar, "sidebar3", "Items")
};

var tab = dt.getVirtualTabs.FirstOrDefault(t => t.Caption == "Sidebar");
if (tab == null)
{
    dt.AddVirtualTab("Sidebar");
    dt.Save();
    tab = dt.getVirtualTabs.FirstOrDefault(t => t.Caption == "Sidebar");
}

foreach (var item in list)
{
    var pt = dt.getPropertyType(item.Item2) ?? dt.AddPropertyType(item.Item1, item.Item2, item.Item3);
    pt.TabId = tab.Id;
    pt.Save();
}