As an emerging technology in the field of electromagnetic manipulation, Reconfigurable Intelligent Metasurfaces (RIS) effectively address the challenges of path loss and transmission distance in terahertz (THz) communications. This paper comprehensively reviews the latest advancements in RIS-assisted THz beam steering technology, with a focus on analyzing the most recent achievements in three major actuation methods: optical, thermal, and electrical control. While optical control boasts non-contact advantages, its flexibility in regulation remains limited. Thermal control, leveraging the Joule effect for heating, still faces challenges in improving control precision and speed. In contrast, electrical control, leveraging the capability of independent unit control, achieves dynamic beam steering with high precision and fast response, fulfilling the requirements of 6G communications. Furthermore, this paper anticipates the future development directions of RIS in this domain, including technical optimization, cost reduction, and enhanced environmental adaptability, thereby providing robust support for the further advancement of THz communications.