Computer graphics in combination with advanced numerical methods can help improvement of many products. One of the not well unexplored examples is design of hot air balloons. However, the design of the 3D shape of the balloon, while being the most important part of the design, is not the end of the design process. Preparation of the balloon fabric cut is a complex process that is critical for quality of the design while still being underestimated and approximated mostly by hand or using very simple tools. This paper addresses the issue of an automatic cut preparation based on the 3D shape and fabric features using means of computer graphics and advanced numerical methods.