book cornersEach book will accept a repaired or replaced page in a different way. Some pages will sit easily into the hinge area, others will slide in from the top or bottom of the text block. Practice putting the page into the book before gluing to see how the page goes in the best.
Often a repaired page cannot be replaced as far back into the spine as when the book was new. If the edges of the repaired or replacement page extend beyond the text block, the page can tear and need future repair.
If the page does not fit correctly in the text block, especially in the case of
replacement pages, trim the height of the page so that the top and bottom
edges will be flush with the edges of the text block. Use a sharp knife and straight edge to trim the margins as scissors will not give a straight edge.
Leave an oversized margin at the fore edge of the page which can be trimmed to the correct size after the page is tipped-in the book.

Several methods can be used to apply glue to a page; practice each one and
see which works best. Often, different techniques will work in different
situations.
1) Using a very small paint brush apply glue to the edge of the page. Do not attempt to use a large brush to apply a small amount of glue. It is very difficult to control a large brush in such a small area and the glue could wind up in all the wrong places.
2) Use a piece of waste paper to mask the inner margin of the page. Leave approximately l/16” exposed of the page exposed. Apply glue across the waste paper toward the edge of the page. Remove the waste paper before placing the page in the book.
3) Apply a l/8” line of glue on a card size piece of thin cardboard or a piece of stiff card stock. Draw the inner edge of the paper along the line of glue making sure the paper edge is covered in a thin, even bead of glue. If the page needs more glue, draw it through the glue again.
If there are some areas that have too much glue and others that are not covered, draw the page over a dry piece of card stock to even out the adhesive.
Once the glue is applied to the page, carefully maneuver the page into the
book. Use the technique that worked best when the page was positioned in
the book before the glue was applied.
Put wax paper directly in front and behind the tipped-in page. Besides
keeping moisture from traveling throughout the book it also protects the
pages from excess glue that can adhere the pages to each other.
Put the repaired book under weight and let dry overnight. When the repair is
dry, carefully remove the wax paper and make sure the page is securely
attached to the book.