Mastoidectomy reconstruction is a complex procedure in which the use of porous hydroxylapatite ceramic wall implant is optimal. Fitting the implant to the operation site requires considerable reshaping of the prosthesis with resultant delays and occasional breakages. The reshaping can be expedited considerably if a metal template is used to obtain the pattern required for the implantation site. A technique using aluminum foil templates to obtain a precise fit is outlined and discussed. The method has been utilized successfully in a series of 42 cases and is recommended to improve the speed and precision of the reconstruction considerably.