The repair kits that are available to repair laminate flooring are designed for minor damages. They will almost always be visible to the person that made the repair. Laminate floor patterns are actually a photo of wood, stone or tile that has a wear layer over it. Major gouges or scratches will probably require that the damaged board will need to be replaced.

The repair kits can work very well with a little experimentation. With many of them you can actually mix different colors to recreate the grain of the wood. (This is not as easy as it sounds, but it can be done.)

For light surface scratches I recommend using a stain pen. There are many different brands available. Simply apply the stain with the pen and immediately wipe-off with your finger. You won't find this in the manufacturer's recommendations, but it does work well. Try it in an inconspicuous area first to make sure you like the result. Keep in mind this is only for surface scratches. Any scratches that actually damage the wear layer will need to be repaired using the repair kit.