The studied careless of this cravat later described as “A lasso like sling round the neck…in its rude freedom” comes from The Art of Tying the Cravat: Demonstrated in Sixteen Lessons (1828).
For more on cravats:
Regency Fashion: Putting on a Cravat – Regency Reader (regrom.com)
Regency Fashion: The Cravat a l’Americaine – Regency Reader (regrom.com)
Regency Fashion: Cravate a la Byron – Regency Reader (regrom.com)
Regency Fashion: Cravate Sentimentale – Regency Reader (regrom.com)
Regency Fashion: The Cravate en Cascade – Regency Reader (regrom.com)
Regency Fashions: Cravate Mathematique – Regency Reader (regrom.com)