In the landscape of Web of Things (WoT), we encounter various WoT platforms. The WoT platforms can collect, manage and mash up a huge mass of things and their data by using Web technologies. Considering heterogeneous things deployed across different platforms, the interoperability issue between things and platforms has been raised as one of major challenges in achieving the vision of the Internet of Things (IoT). In this paper, we propose a Semantic Service Description (SSD) ontology to guarantee the semantic consistency of a service description. We also present an approach to generating a service description and deploying a set of heterogeneous things to different platforms automatically. Through the implementation of a prototype, the applicability of our proposal is demonstrated and the experimental results are discussed.