This paper provides a solution for design of permanent magnet (PM) assisted synchronous reluctance machine (PMa-SynRM). Unlike interior PM machines, the PMa-SynRM is substantially a SynRM with a dominant reluctance torque. PMa-SynRMs are often designed by direct embedding magnets in a SynRM rotor to improve the performance over the original SynRM. However, the PM arrangements being more effective to motor performance have not been fully discussed. This paper investigates the influence of several key factors concerning the PMs embedded. The torque, PM flux linkage, flux linkage on d-q axis and power factor are evaluated. Based on the analysis, a guideline is proposed for determination of PM sizes and layers in PMa-SynRM design. Finite element analysis (FEA) is used to evaluate the performance. Finally, experimental studies are conducted to validate the proposed method.