A method of controlling a transition from a laminar flow to a turbulent flow for an airfoil of a turbomachine includes forming an airfoil. The airfoil defines a span extending between a root and a tip and a chord extending between a leading edge and a trailing edge. The airfoil includes a suction side surface and a pressure side surface, opposite the suction side surface, each extending between the leading edge, the trailing edge, the root, and the tip. The method also includes finishing a majority of the suction and pressure side surfaces in order to form a finished surface. The finished surface defines a first roughness. The method additionally includes leaving at least a portion of the suction side surface and/or pressure side surface unfinished in order to form an unfinished surface. Furthermore, the unfinished surface defines a second roughness greater than the first roughness.