Hello, I have paid a builder to sand and seal my interior oak wood floor. However, one walk on it and it’s dirty already (dusty) and that smudges when I try to wipe clean. I understand I should not use water to clean. How should i clean it And i would like to add a top coat of varnish so it is easier to clean In the future. What type of varnish should i Use, and how many coats? Thanks