If you have scratched the wood varnish in your home you will want to make sure that you fix it quickly as it is noticeable. Here are a few steps that will help you through the process painlessly.
Step 1 - Repairing a Tiny Scratch
If the scratch is more taking the color off rather than wood being removed then there are a couple of options for you. The first option would be to find and test out a pen or marker that is the same color as the wood and you can use it to color in the scratch and then use a paint brush to put varnish over it. If you do try this method you will want to test out the marker in a place that is not out in the open for everyone to see. Try a corner or somewhere hidden. Almond oil can also be used to repair small or light scratches. All you need to do is take an almond oil stick and rub it on the wood until it fills and then after you can coat with varnish to cover it up.
Step 2 - Repairing Dents
A wood filler can be used for bigger dents. The first thing to do is remove anything with a wood stripper and a cotton ball or several. Then take a clean and damp rag or washcloth and place it over the dent and use the iron to heat the area by running it over the wash cloth. Then use the wood filler in this spot and repeat the ironing process. Once you are done you can even it out with sand paper and then use a stain and varnish to finish it off.
Step 3 - Repairing Deep Scratches
Bigger scratches will take a little more effort than just a light scratch or dent. In a bowl, blend a drop of lacquer thinner with denatured alcohol and use the paint brush to paint into the scratch and the area around it so that it all blends in together. Once the area is completely dry and smooth you can apply a coat or two of lemon oil. If this method doesn't help the first time around, you can use the same mixture but then instead of using a paintbrush you can use the edge of a blade to dig it into the scratch and then let dry and smooth out and then layer on the lemon oil afterward.
If this method seems too lengthy and you are looking for a quicker fix you can try out a furniture repair stick. This will often work but may not last as long as the above method. After each method though you will want to stain the wood again and then re varnish.
Depending on the degree of the scratch be sure to use the proper method and good luck!