Disclosed is a method for producing an aldehyde crosslinked polyacrylamide composition useful for strengthening paper. The method includes steps, wherein a) an aldehyde crosslinker and polyacrylamide are mixed in water to form an aqueous solution of aldehyde crosslinked polyacrylamide prepolymer; b) acid is added to the aqueous prepolymer solution to adjust the pH of the solution to a value between 1 to 5; c) storing and transporting the prepolymer solution to the location where the final glyoxalated polyacrylamide composition will be used; and d) adding a base to the stabilized prepolymer solution to adjust the pH of the solution to value between 5.5 to 12, and e) allowing the aldehyde crosslinker and polyacrylamide contained in the aldehyde crosslinked polyacrylamide prepolymer solution to react further and form aldehyde crosslinked polyacrylamide composition useful for strengthening paper.