The Hybrid Elevated Radio Observatory for Neutrinos (HERON) is designed to target the astrophysical flux of Earth-skimming tau neutrinos at 100 PeV. HERON consists of multiple compact, phased radio arrays embedded within a larger sparse array of antennas, located on the side of a mountain. This hybrid design provides both excellent sensitivity and a sub-degree pointing resolution. To design HERON, a suite of simulations accounting for tau propagation, shower development, radio emission, and antenna response were used. These simulations were used to discover the array layout which provides maximum sensitivity at 100 PeV, as well to select the optimal antenna design. Additionally, the event reconstruction accuracy has been tested for various designs of the sparse array via simulated interferometry. Here, we present the HERON simulation procedure and its results.