Some books lie open easily (most magazines and worn books, for
example), but some are bound so tightly that their pages have to be
held open in order to read them. I have several bookholders but have
found the easiest way to hold pages down is with another book. A good
magazine like "Playboy" is best for this because it is heavy and slides
easily. Also, the bound edge is sort of beveled, which makes page
insertion underneath it easy.