<human>:  How do I properly sand and varnish a hardwood floor?
<bot>: 
1. Start by preparing the floor. This can include sanding down bumps and ripples, filling in any divots or cracks, and cleaning the surface of any dirt.
2. Once the floor is prepped and you’re ready to begin, you’ll need to sand it. Start with a coarse sandpaper and work your way up to a finer grade.
3. After sanding, you’ll need to clean the dust and residue from the floor with a damp cloth. Then, you can apply a coat of clear sealer or varnish to the floor.
4. Allow the sealer or varnish to dry before applying a second coat. After that coat has also dried, you can apply a third coat if desired.
5. Finish off the floor with a protective topcoat, and you’re good to go!