In this procedure, referred to as guarding, strips of Japanese tissue are adhered to the folds with a starch paste. This refers to the fastening together of the pages of a book with thread. Several techniques are used in conservation binding. The sections are then sewn to each other with thread. Often sections are sewn to sewing supports such as tapes or cords.
Unbleached linen is the type of thread most frequently selected by conservators.
Original boards are reattached to the sewn pages using new leather, cloth, or paper dyed to blend with the original covering material. The new material is worked under the original at the joints, and the fragments of the spine covering of the original binding are adhered to the surface of the new spine material. For lightweight books a case structure is adequate. The case is most frequently covered in cloth, although it can be covered in paper or leather as well. This structure is most often chosen for medium to large books because it provides adequate support for them.