A method for determining the degree of twist to be manually introduced into an implant which is to be positioned in the aorta and adjacent iliac branches so as to achieve an effective degree of twist when the implant is positioned in the anatomy, the method comprising: identifying the effective degree of twist desired for the implant; determining the Native Iliac Rotation of a patient; and subtracting the Native Iliac Rotation of a patient from the effective degree of twist desired for the implant so as to determine the degree of twist to be manually introduced into the implant.