Data Access Objects and Entity Relationships

What is the proper way to structure DTO's for my tables?

Three of my tables are Documents which contains Pages and Fontstyles. I am creating an EditDocument view in which I will edit these (and more) tables related to document.

I thought of a solution, but I'm not sure if this is the proper way to do it. I'm just a beginner and just starting with dependency injection so, I might need some help on that too. what are your thoughts?

Create a List< fontStyleDTO > and List< PagesDTO > within DocumentDTO which contains the pages and fonts

public class DocumentDTO
{
    public DocumentDTO (List<FontStyleDTO> fontStyles, List<PageDTO> pages) {
        _fontStyles = fontStyles;
        _pages = pages;
    }

    public List<FontStyleDTO> Pages {
        get { return _pages; }
    }

    public List<PageDTO> FontStyles {
        get { return _fontStyles; }
    }
}

If I would want to add a page to the document I would do:

document.Pages.Add(page)

And then via the OR-mapper in the database:

public class DocumentDTOIntoDatabase
{

    public DocumentDTOToDatabase (DTODocument document, DocumentMapper documentMapper) {
       _document = document;
       _documentMapper = documentMapper;
    }

    public AddDocumentToDatabase() {
        Document ormDocument = _documentMapper.FindById(document.id)
        ormDocument.name = document.name;
        //etc...
        AddPagesToDocument(document.pages, ormDocument)
        ormDocument.save
    }

    public AddPagesToDocument(List<PageDTO> pages, Document ormDocument) {
        foreach (var page in document.Pages) {                
            ormDocument.Pages.Add(convertToOrmPage(page))
        }
    }
}