When attempting to clean paper, always start with the least abrasive cleaning method before trying others. Keep in mind that cleaning can be a time consuming task. Evaluate each book before attempting to dry clean it. Make sure that cleaning a particular volume is a good use of time.
Dry cleaning is any kind of cleaning that does not use water or liquid cleaners. Done correctly, dry cleaning will not damage your book.

Brushes

Some dirt can be swept off the page using a soft, natural bristle brush. Always brush from the center of the page out toward the edges in a star burst pattern and up and down the hinge area to remove dirt or eraser crumbs.
Brushes can be of any size but should have soft, natural bristles. Plastic or nylon bristles can scratch the paper. Brushes used for dry cleaning should not be used for water, paste or glue so it’s best to designate a brush just for dry cleaning.

Watch out for paper tears that can catch on the brush and NEVER brush from the edge of the paper toward the middle. The brush could “grab” the edge of the page, pull it back on itself and cause a tear. This is especially important to remember when there are small tears on the edge of the page.

After using a dry brush to sweep off the surface dirt, products such as Opaline or Skum-X can be used to remove more stubborn surface dirt. Opaline and Skum-X are both eraser products. Opaline comes in a bag and Skum-X in a shaker dispenser. Opaline is applied by kneading the bag above the paper until the paper is covered with a fine powder of tiny eraser crumbs. Skum-X is applied like salt from a salt shaker.

Using clean fingers, rub the paper lightly in a circular pattern. DO NOT RUB THE PAPER WITH THE OPALINE CLOTH BAG or the bag will become soiled quickly and transfer that dirt onto the page. It is possible to protect the page from skin oil by rubbing through a soft cloth or a piece of polyester film, such as Mylar.

ALWAYS work in a circular motion from the center of the page toward the outside edge. Be very careful of the edges of the page; they tear easily.
The eraser crumbs change color as they pick up dirt. Once they seem to have picked up as much dirt as possible, brush the eraser crumbs off the page. Use a natural bristle brush to sweep the eraser crumbs off the page. Brush from the center of the page toward the edge of the paper and don’t forget to sweep the eraser crumbs out of the hinge area. If the page is still dirty, repeat the procedure. When the eraser crumbs do not change color, they have picked up as much dirt as possible.

What about pencil or pen notations on the page of a book?

While most pens are permanent, some pencil marks can be erased from paper. A white vinyl eraser, such as Faber Castel or Magic-Rub eraser, is recommended because it is less abrasive than most other erasers. These vinyl erasers come in several sizes and can be shaped with a knife or purchased in a pencil form and sharpened to reach small areas or between lines of print.
Erase in one direction, working from the center of the paper toward the edges of the paper. DO NOT rub the eraser back and forth or erase from the edge of the paper toward the center of the book.
Use a natural bristle brush to sweep away the eraser crumbs, paying special attention to removing eraser crumbs from the inner margin of the page.
Remember to brush from the center of the page toward the edge