Experience counts when it comes to good hardwood floor refinishing. That said, most weekend warriors can manage a decent job as long as they avoid the common mistake many DIYers make. Homeowners typically skimp on the sanding for fear of damaging the wood. The result is that when varnished, the refinished floors may appear uneven where old finish remains. Instead, be sure to work conscientiously from coarse to medium to fine sandpaper for a thorough job that will yield floors with a pristine finish.