This study, using the Longwangxi slope in Yunyang as an example, investigates the deformation characteristics of various slope areas through field investigation, engineering analogy, and numerical simulation. The monitoring plan was designed based on these analyses, with monitoring equipment deployed to collect data on surface and deep cumulative displacements in active deformation regions. The real monitoring data validated the conclusions drawn from the engineering analogy and numerical simulation. This research demonstrates that a combination of field investigation, engineering analogy, and numerical simulation can provide practical monitoring indicators and spatial layout for slope monitoring design. For deep accumulated slopes with underlying bedding bedrock, a comprehensive monitoring system that includes surface displacement, deep displacement, and rainfall should be established. The surface displacement is mainly distributed at the slope's front edge, while deep displacement is significant in the middle of the slope, where the soil-rock interface inclination is gentle, and the accumulation body is thick.