There are times when the dust caused by sanding can be a problem, such as when the dust can get into sensitive electronic equipment, or when the dust might contain lead or other contaminants. Dust can be eliminated by wet sanding.
Purchase sandpaper especially designed for wet sanding in different grits appropriate to your particular project (60-grit and 150-grit are common). Purchase a hard rubber sanding block. Attach courser sandpaper (60-grit) to sanding block as per manufacturer's directions.
Dip sanding block into a bucket of water or thoroughly spray water onto surface to be sanded. Sand in normal fashion, sanding with the grain of the wood.
Frequently wipe down project with squeegee. This will allow you to gauge your progress. Wipe squeegee clean and keep all wet sanded debris cleaned as you go. If sanded material dries, it will be extremely difficult to remove.
Switch to finer grit paper (150-grit) once the project is relatively smooth. Dunk paper into water or spray area to be sanded. Sand with the grain. Again, frequently squeegee in order to both monitor progress and to clear away sanded material. Frequently clean all sanded material.
Sand with finer and finer grits of paper, always keeping paper and project wet, until the desired smoothness has been achieved. Squeegee project as clean as possible. Wipe project down with damp sponge then wipe with tack cloth and allow to dry. Clean area with wet-dry shop vac.