It is not straightforward for beginners in quantum chemistry to understand how to obtain numerical results from abstract theoretical formulae. Therefore I wrote this small tutorial during 2009 to 2012, discussing in detail on how to carry out an actual Hartree-Fock, configuration interaction, coupled-cluster, time-dependent/independent density functional theory, geometry optimization or Hessian calculation using H2 as example. It therefore was also known as "Understanding Quantum Chemistry from H2MODEL" several years ago.