A computer-aided design system enables physical articles to be customized via printing or embroidering and enables digital content to be customized and electronically shared. A user interface may be generated that includes an image of a model of an article of manufacture and user customizable design areas that are graphically indicated on the image corresponding to the model. A design area selection may be received. In response to an add design element instruction and design element specification, the specified design element is rendered in the selected design area on the model image. Customization permissions associated with the selected design area are accessed, and using the customization permissions, a first set of design element edit tools are selected and rendered. User edits to the design element may be received and rendered in real time. Manufacturing instructions may be transmitted to a printing system.