A method of aligning a cutting trajectory of a flat element with respect to a selected graphic pattern on said flat element, comprising the steps of: - providing a working file wherein are stored the initial spatial coordinates of the trajectory defining the cutting trajectory with respect to a reference system, the graphic pattern coordinates defining the position of said selected graphic pattern with respect to the cutting trajectory, and graphic pattern coordinates defining the position of additional graphic patterns; - positioning by an operator the flat element to be cut on a support table; - projecting onto the flat element, by means of a projector device, the image of a reference figure uniquely associated with the coordinates of the cutting trajectory and/or the coordinates relative to the selected graphic pattern; - framing, by means of a camera, at least a portion of the flat element wherein there is present at least a part of the selected graphic pattern and at least a part of said image of the reference figure; - displaying on a monitor the image framed by the camera and a virtual image of the selected graphic pattern and of the additional graphic patterns defined by the coordinates relative to the respective graphic patterns; - moving the image of the reference figure or the virtual image of the selected graphic pattern until a portion of the said virtual image of the selected graphic pattern coincides with the corresponding real image of the selected graphic pattern taken by the camera; - displaying on the monitor the displacement of the image of the cutting trajectory in the position resulting from the movement of the reference figure with respect the image of the additional graphic patterns. - providing a working file wherein are stored the initial spatial coordinates of the trajectory defining the cutting trajectory with respect to a reference system, the graphic pattern coordinates defining the position of said selected graphic pattern with respect to the cutting trajectory, and graphic pattern coordinates defining the position of additional graphic patterns; - positioning by an operator the flat element to be cut on a support table; - projecting onto the flat element, by means of a projector device, the image of a reference figure uniquely associated with the coordinates of the cutting trajectory and/or the coordinates relative to the selected graphic pattern; - framing, by means of a camera, at least a portion of the flat element wherein there is present at least a part of the selected graphic pattern and at least a part of said image of the reference figure; - displaying on a monitor the image framed by the camera and a virtual image of the selected graphic pattern and of the additional graphic patterns defined by the coordinates relative to the respective graphic patterns; - moving the image of the reference figure or the virtual image of the selected graphic pattern until a portion of the said virtual image of the selected graphic pattern coincides with the corresponding real image of the selected graphic pattern taken by the camera; - displaying on the monitor the displacement of the image of the cutting trajectory in the position resulting from the movement of the reference figure with respect the image of the additional graphic patterns.