We describe a novel performance optimization method for all-optical amplitude reshaping via degenerated four-wave mixing (FWM) in highly nonlinear optical fiber. The proposed optimization method is achieved by judiciously configuring the FWM operational condition and exploiting the nonlinear phase shift induced by self- and cross-phase modulations to properly influence the FWM conversion efficiency. Through the proposed scheme, fully functional and prevailing reshaping performance, including significant amplitude jitter suppression and extinction ratio improvement, is obtained within a single FWM stage. Results of the present theoretical calculation and numerical simulation verify the feasibility and advantages of the proposed scheme.