Clean the furniture
Before fixing a scratch, you need to clean the furniture thoroughly. First you are required to make a cleaning solution. Take a deep bowl or a bucket with one gallon or 3.8 litres of water and add mild dish washing soap as you mix it. Next, take a lint-free cloth and after dipping it in the bucket, you need to rinse out all the excess water. You can now use this to clean your furniture by wiping the wood. Focus on a small area first and clean it by rubbing it with the cloth. After cleaning the wood furniture you should allow it to completely dry.
Felt-tip marker method
Get felt-tip markers from your local wood, home improvement or hardware store. Later you need to apply it on the scratches. In case you accidentally mark on the finished surface then you need to clean it quickly.
Paste of coffee and water
In order to make the paste you need to take a bowl and add a tablespoon of coffee granules to it. Then add a small amount of water which will make a thick paste. Later you need to apply the paste on the scratched surface. Apply the paste carefully so it does not fall on the surrounding wood surface. Make sure to wipe off any excess paste. Do this with the help of a dry cloth.
You can also apply a shelled walnut on the scratches. The oil from the walnut will make scratches much lighter, eventually diminishing them.
In order to fix scratches on very dark wood, you can apply Iodine. Simply take a cotton swab and directly apply Iodine on the surface.