Method of manufacturing paper or cardboard comprising the steps of Addition of a water-soluble polymer P to a first aqueous pulp suspension having a dry content of between 0.1% and 6% by weight, resulting in a second aqueous pulp suspension containing polymer P, where the polymer P is obtainable by - radical polymerization to form a polymer V of (i) 33 to 83 mol% of a monomer of Formula I in which R 1 = H or C 1 -C 6 -Alkyl, (ii) 6 to 56 mol% diallyldimethylammonium chloride, diallyldiethylammonium chloride or a salt form of a monoethylenically unsaturated monomer with a quaternized nitrogen as the sole charge-carrying group at a pH of 7, (iii) 11 to 61 mol% of a monoethylenically unsaturated carboxylic acid, a monoethylenically unsaturated sulfonic acid or a monoethylenically unsaturated phosphonic acid, or salt forms thereof, (iv) 0 to 50 mol% of one or more ethylenically unsaturated monomers, other than a monomer (i), (ii) and (iii), the total amount of all monomers (i), (ii), (iii) and (iv) being 100 mol%, and - Hydrolyzing the N-C(=0)R 1 groups of the units of the monomers of the formula polymerized into the polymer V to form primary amino or amidine groups to give the polymer P, at least 87% of the units of the monomers of the formula polymerized into the polymer V being hydrolyzed, based on the number of all units of the monomers of the formula I polymerized into the polymer V, Dewatering the second aqueous pulp suspension containing polymer P on a water-permeable support to form a wet paper structure which has a dry content of between 18.5% and 25% by weight, Dewatering of the wet paper structure, resulting in the paper or cardboard. Addition of a water-soluble polymer P to a first aqueous pulp suspension having a dry content of between 0.1% and 6% by weight, resulting in a second aqueous pulp suspension containing polymer P, where the polymer P is obtainable by - radical polymerization to form a polymer V of (i) 33 to 83 mol% of a monomer of Formula I in which R 1 = H or C 1 -C 6 -Alkyl, (ii) 6 to 56 mol% diallyldimethylammonium chloride, diallyldiethylammonium chloride or a salt form of a monoethylenically unsaturated monomer with a quaternized nitrogen as the sole charge-carrying group at a pH of 7, (iii) 11 to 61 mol% of a monoethylenically unsaturated carboxylic acid, a monoethylenically unsaturated sulfonic acid or a monoethylenically unsaturated phosphonic acid, or salt forms thereof, (iv) 0 to 50 mol% of one or more ethylenically unsaturated monomers, other than a monomer (i), (ii) and (iii), the total amount of all monomers (i), (ii), (iii) and (iv) being 100 mol%, and - Hydrolyzing the N-C(=0)R 1 groups of the units of the monomers of the formula polymerized into the polymer V to form primary amino or amidine groups to give the polymer P, at least 87% of the units of the monomers of the formula polymerized into the polymer V being hydrolyzed, based on the number of all units of the monomers of the formula I polymerized into the polymer V, - radical polymerization to form a polymer V of (i) 33 to 83 mol% of a monomer of Formula I in which R 1 = H or C 1 -C 6 -Alkyl, (ii) 6 to 56 mol% diallyldimethylammonium chloride, diallyldiethylammonium chloride or a salt form of a monoethylenically unsaturated monomer with a quaternized nitrogen as the sole charge-carrying group at a pH of 7, (iii) 11 to 61 mol% of a monoethylenically unsaturated carboxylic acid, a monoethylenically unsaturated sulfonic acid or a monoethylenically unsaturated phosphonic acid, or salt forms thereof, (iv) 0 to 50 mol% of one or more ethylenically unsaturated monomers, other than a monomer (i), (ii) and (iii), the total amount of all monomers (i), (ii), (iii) and (iv) being 100 mol%, and (i) 33 to 83 mol% of a monomer of Formula I in which R 1 = H or C 1 -C 6 -Alkyl, (ii) 6 to 56 mol% diallyldimethylammonium chloride, diallyldiethylammonium chloride or a salt form of a monoethylenically unsaturated monomer with a quaternized nitrogen as the sole charge-carrying group at a pH of 7, (iii) 11 to 61 mol% of a monoethylenically unsaturated carboxylic acid, a monoethylenically unsaturated sulfonic acid or a monoethylenically unsaturated phosphonic acid, or salt forms thereof, (iv) 0 to 50 mol% of one or more ethylenically unsaturated monomers, other than a monomer (i), (ii) and (iii), the total amount of all monomers (i), (ii), (iii) and (iv) being 100 mol%, and - Hydrolyzing the N-C(=0)R 1 groups of the units of the monomers of the formula polymerized into the polymer V to form primary amino or amidine groups to give the polymer P, at least 87% of the units of the monomers of the formula polymerized into the polymer V being hydrolyzed, based on the number of all units of the monomers of the formula I polymerized into the polymer V, Dewatering the second aqueous pulp suspension containing polymer P on a water-permeable support to form a wet paper structure which has a dry content of between 18.5% and 25% by weight, Dewatering of the wet paper structure, resulting in the paper or cardboard.