Sand for a perfect finish
Start smooth to end smooth
After finish-sanding the bare wood of your project, typically to 220 grit, vacuum the surface to remove embedded dust; then, wipe the surface with a clean rag dipped in mineral spirits. Allow the surface to dry thoroughly.
Apply the first coat of finish to your project and let it dry completely. In a well-lit area, buff out the first coat with 220-grit stearated (abrasive loaded with a dry lubricant) or open-coat (half the amount of abrasive grain leaves room for the loading of material) abrasive. Use long, straight strokes parallel to the grain, applying light, even pressure and overlapping each stroke. The finish can rub through to bare wood most easily on the edges of the workpiece, so ease up on your pressure when sanding these areas.
After making a complete pass with the abrasive, wipe down the workpiece with a clean rag and feel for smoothness. Your finish will appear dull or slightly scratched after sanding, but the next coat of finish will restore its luster. Buff out the second coat like the first, using 320-grit paper, then recoat and repeat, ending with 800 grit.
Real (and unreal) steel does the trick
Ordinary sandpaper clogs quickly with gummy finish when buffing between coats, leaving erratic scratches and increasing sanding time. Instead, use steel wool or a synthetic substitute to achieve results similar to sandpaper but without clogging. Just remember that #00 steel wool generally yields similar results to 360-grit sandpaper, #000 equates to 400 grit, and #0000 equates to 600 grit. Because synthetic steel-wool pads are typically labeled with ambiguous designations such as "ultra fine," "general purpose," and "heavy duty," drawing accurate comparisons to other abrasives is difficult. Try them on a test piece before using them on your workpiece.