Here’s a great old tip that’s worth revisiting. Can’t tell where you’ve sanded and where you haven’t? Scribble light pencil lines over the surface, and then sand away until they’re gone. You’ll sand the entire surface without missing a spot, even out hard-to-see high and low areas, and know when to switch to a finer grit of sandpaper. The finer the grit, the lighter the pencil lines should be. It’ll take for-ever to sand off dark lines with fine grits.
Our thanks to Karen Dybdahl for this very smooth tip.