We propose an algorithm for generating a Priority Rewrite System (PRS) for an arbitrary process language in the OSOS format such that rewriting of process terms is sound for bisimulation and head normalising. The algorithm is inspired by a procedure which was developed by Aceto, Bloom and Vaandrager and presented in Turning SOS rules into equations [2]. For a subclass of OSOS process languages representing finite behaviours the PRSs that are generated by our algorithm are strongly normalising (terminating) and confluent, where termination is proved using the dependency pair and dependency graph techniques. Additionally, such PRSs are complete for bisimulation on closed process terms modulo associativity and commutativity of the choice operator of CCS. We illustrate the usefulness of our results, and the benefits of rewriting with priorities in general, with several examples.