Human visits to the Moon will be the next milestone for human space exploration. During deep space crewed missions, radiation risk is an important and unavoidable risk for astronauts' health, especially for their long-term stays at future lunar stations. In this work, we present the first protocol of a lunar mission schedule given space radiation constraints. We use the recently developed and validated "Radiation Environment and Dose at the Moon (REDMoon)" model [1] to calculate radiation dose rates due to omnipresent Galactic Cosmic Rays (GCR) and sporadic Solar Energetic Particles (SEP) as well as the secondary particles induced by them at the surface and subsurface of the Moon. We evaluate the biologically-weighted body effective dose rate, its variation with solar activity, and its dependence on the shielding thickness, including both the lunar soil shielding and the module aluminum shielding. For surface bases assuming a historical solar activity period (e.g., that between year 2000 and 2020), we obtain the background GCR exposure rate to be 20-40 cSv . year-1 considering different solar modulation conditions and various Al-shielding thicknesses of the module. In comparison, the average radiation exposure for an astronaut in International Space Station at low-Earth orbit is ≈20 cSv . year-1 in the middle of solar cycle in 2006 [2]. Large SEP events throughout this period are also accounted for and some single-event effective dose may exceed the annual GCR level if shielding is insufficient. We thus consider potential bases utilizing in-situ lunar regolith for shielding protection. We investigate different combinations of depth and Al-shielding for lunar base scenarios to derive mission schedules which allow the persistent presence of crew operation on the Moon. With our schedule throughout the aforementioned period, the radiation exposure is kept under certain recommended levels. As a first protocol, our work provide valuable radiation mitigation considerations for future human lunar bases and mission cost estimates.