A method is provided for automatically modifying the cutting paths for parts to be cut out from a flexible material by automatically moving a cutter tool along predetermined cutting paths. The cutting paths are associated with each part being defined by a succession of cutting segments forming a polygon. Two cutting segments are identified and belonging to two different parts for cutting out in the material and for which a maximum distance condition between these cutting segments is satisfied. Two cutting segments are verified for being situated facing each other, and that no other cutting segments lie between the two cutting segments. A common cutting path for the two cutting segments is computed, and a common cutting path is connected to the cutting paths of the two parts for cutting out to obtain modified cutting paths for the two parts for cutting out.