In the cell nucleus, chromosomes have a complex spatial organization, spanning several length scales, which serves vital functional purposes. It is unknown, however, how their three-dimensional architecture is orchestrated. In the present article, we review the application of a model based on classical polymer physics, the strings and binders switch model, to explain the molecular mechanisms of chromatin self-organization. We explore the scenario where chromatin architecture is shaped and regulated by the interactions of chromosomes with diffusing DNA-binding factors via thermodynamics mechanisms and compare it with available experimental data.