When you have reached this step, expand the Applications subsection in the tree by clicking on the triangle next to it, and check element X11. Continue using the buttons at the bottom until you reach the installation type step. Double-click it.Īn installer window will appear. Insert your OS X install disk and locate the Optional Installs package. This guide will guide you through installing GIMP on mac OS X 10.5.x with easy-to-follow and clear instructions.