Dado o código a seguir, como posso passar dados de "Primeiro nome", "Sobrenome" etc. para o meu métodoBookASession.SendMessage();?

RootElement CreateBookASessionRoot() 
{
    return new RootElement("Book a Session") {
        new Section() {
            new EntryElement("First Name", "First Name", ""),
            new EntryElement("Last Name", "Last Name", ""),
            new EntryElement("Email", "Email", "") { KeyboardType = UIKeyboardType.EmailAddress },
            new DateElement("Event Date", DateTime.Now),
            new RootElement ("Type of Shoot", new RadioGroup (0)){
                    new Section (){
                        new RadioElement("Wedding"),
                    new RadioElement("Portrait"),
                    new RadioElement("Boudoir"),
                    new RadioElement("Other")
                    }
            } ,
            new EntryElement("Message", "Message", "")
        } ,
        new Section () {
            new StringElement("Send", delegate { BookASession.SendMessage(); } )
        }
    };                      
}