For the piecing of a yarn in an spinning device, various computation formulas are stored in a control device into which calculated values as well as special data converted into numerical values relating in particular to the fiber material, the yarn and the spinning element are first entered to compute and select settings for operations relevant to the piecing process. A feeding device feeding a fiber sliver to the spinning device is first brought to a high pre-feeding speed by means of such pre-programmed values and converted data. From this pre-feeding speed, the feeding speed is greatly decelerated in steps to its piecing feeding speed in coordination with the release of the yarn to be fed back into the spinning element.