Method for shaping a flat web material, wherein the flat web material is largely flat or smooth and level in the initial state and, when folded in a final state, is in a regular three-dimensional structure with a multiplicity of folds along differently oriented folding lines (14, 14') and with elevations and depressions, the method having the following steps: - the flat web material is inserted between a lower holding die and an upper holding die, wherein the holding dies are composed of flat material and have pre-formed kink lines (22a, 22b) which are identical on the two holding dies and along which the holding dies are deformable, and which lie precisely one above the other when they are resting on the flat web material, - moving a lower shaping die from below and an upper shaping die from above up to the holding dies (20a, 20b), wherein the shaping dies (30a, 30b) are composed of flat material with predetermined bending lines (32a, 32b), - the holding dies (20a, 20b) are largely level during the insertion of the flat web material and also as the shaping dies (30a, 30b) are moved up, - the shaping dies (30a, 30b) have bending lines (32a, 32b) which correspond precisely to one another or lie precisely opposite one another, with identical bending along the bending lines (32a, 32b), wherein the shaping dies (30a, 30b) are not flat, but are raised by bending along the bending lines (32a, 32b) or have a shape corresponding to the three-dimensional structure to be produced with the flat web material, wherein at least some of the bending lines (32a, 32b) of the shaping dies (30a, 30b) coincide with kink lines (22a, 22b) of the holding dies (20a, 20b), in particular those bending lines (32a, 32b) of the shaping dies (30a, 30b) which are oriented toward or point toward the holding dies (20a, 20b) and can come to rest thereon. - the flat web material is inserted between a lower holding die and an upper holding die, wherein the holding dies are composed of flat material and have pre-formed kink lines (22a, 22b) which are identical on the two holding dies and along which the holding dies are deformable, and which lie precisely one above the other when they are resting on the flat web material, - moving a lower shaping die from below and an upper shaping die from above up to the holding dies (20a, 20b), wherein the shaping dies (30a, 30b) are composed of flat material with predetermined bending lines (32a, 32b), - the holding dies (20a, 20b) are largely level during the insertion of the flat web material and also as the shaping dies (30a, 30b) are moved up, - the shaping dies (30a, 30b) have bending lines (32a, 32b) which correspond precisely to one another or lie precisely opposite one another, with identical bending along the bending lines (32a, 32b), wherein the shaping dies (30a, 30b) are not flat, but are raised by bending along the bending lines (32a, 32b) or have a shape corresponding to the three-dimensional structure to be produced with the flat web material, wherein at least some of the bending lines (32a, 32b) of the shaping dies (30a, 30b) coincide with kink lines (22a, 22b) of the holding dies (20a, 20b), in particular those bending lines (32a, 32b) of the shaping dies (30a, 30b) which are oriented toward or point toward the holding dies (20a, 20b) and can come to rest thereon.