Mina Himwich of Princeton University's Program in Theoretical Physics (PCTS) continues a two part introduction to celestial holography, delivered as part of the Institute for Advanced Study's Prospects in Theoretical Physics 2026 summer program. This second session builds on foundational material to develop the celestial holography framework, which recasts scattering amplitudes in asymptotically flat spacetime as correlators of a conformal field theory living on the celestial sphere. Himwich works through the technical machinery connecting bulk gravitational and gauge theory physics to boundary observables, aimed at graduate students and researchers already versed in quantum field theory and general relativity. The talk runs 82 minutes and is pitched at the level of a specialized summer school lecture rather than a general audience introduction, with blackboard or slide derivations carrying most of the argument.