Choose a putty filler that matches your laminate flooring best. Bringing a scrap piece of laminate flooring with you when you make the purchase will help you make the perfect match.
Apply a solvent-based cleaner to a soft cleaning cloth and rub it over the affected area. Mineral spirits and denatured alcohol are both solvents that prepare the surface of the laminate flooring for repair. Some putty manufacturers prefer a certain type of solvent for this purpose, so check the label beforehand.
Squeeze a dollop of laminate floor putty filler onto a piece of cardboard. Scoop a small amount of the putty filler onto the putty knife provided by the manufacturer.
Use the edge and bottom of the putty knife to press the putty filler into the crack. Run the putty knife over the crack several times to smooth the putty filler.
Remove excess putty filler from the laminate flooring using a soft cloth dampened with cleaning solvent. Rub the damp cloth over and around the repaired area, rendering the repaired crack unnoticeable.
Wait approximately two hours before walking over the repaired area of laminate flooring. Most putty fillers harden within two hours and completely cure within six to eight hours.