What is the best technique for sanding hardwood floors with an orbital sander?

The best technique for sanding hardwood floors with an orbital sander is to start with a coarse grit sandpaper to remove old finish and imperfections, then gradually switch to finer grits for a smoother finish. Move the sander in a consistent, overlapping pattern, going with the grain of the wood. Be sure to vacuum or sweep between grit changes to remove dust and debris.