In response to the person-to-person contact service design, the work aims to strengthen the visualization effect of the duration of each service step in the service blueprint, so that designers could effectively identify the optimization opportunity, make reasonable design decisions, and improve the service quality. Based on the service blueprint tool, the evolving process and research status of current service blueprint were investigated through literature review. It was found that existing service blueprint tools did not consider the impact of time factor on service quality. Second, the time visualization form of the time management tool Gantt chart was introduced to optimize the current service blueprint tool. Finally, the reliability and reasonability of the new tool were verified through a case "outpatient medical service of a hospital". The new tool's effectiveness, satisfaction and efficiency were evaluated through Usability Metric for User Experience. Based on the main functions of current service blueprint, a new timeline service blueprint tool was posed for the tangible services that directly act on human body. It is concluded from the article that the new timeline service blueprint is helpful for designers to clarify the impact of the duration of each step, which could help capture experience optimization opportunity accurately. Therefore, the user experience of tangible service could be improved.