The method serves for expanding and formatting profiled metal strip material (1) to form a netting-like mat structure (2) of a predeterminable mesh width by a continuous drawing-open process. For this purpose, the strip material (1) is provided with notches (3), which extend in the longitudinal direction of the strip, are of a limited length and between them form metal strands (11), wherein, after the expanding and formatting, the unnotched regions form netting nodes (4) and initially the metal strands (11) are connected to one another by way of adjoining webs in the base of the notch. The webs have fatigue-fracture induced incipient tears formed by flexural deformation. The remaining web is then severed by a separating roll, so that the metal strands (11) are reliably separated from one another in the notch region and the strip material (1) can be drawn open to form the netting-like structure. The strip material (1) is first drawn open at the beginning of the strip to the intended mesh width in such a way that some rows of mesh are aligned orthogonally and oriented at right angles to the edge of the strip with respect to their mesh diagonal. The prepared beginning of the strip is placed with the meshes onto the spikes (5) of a spiked roll (5.1) of a pair of rolls (5), after which the pressure roll (5.2) of the pair of rolls (5) is infed towards the spiked roll (5.1) and with it forms a rolling gap. In this case, the arrangement of the spikes (6) is chosen such that every second mesh—in both orthogonal directions—is shaped by a spike (6), in that the spikes (6) of the spiked roll (5.1) enter the clearances (7) in the pressure roll (5.2).