You can be creative using very special materials, or you can use just about anything.
The hand-made books in these pictures contain pages made out of, among other things, brown paper bags that once held groceries and envelopes from the bank and the tax office (I wanted to see if I could make myself love them, and I enjoyed using their unusual shapes and sizes to make fold-out pages). The covers are made of a wallpaper sample and brown corduroy from a pair of my old trousers. The teatime-themed pattern printed on the endpaper is made from a printing stamp that I carved into a children's eraser. Sometimes I use shop-bought PVA glue, and sometimes I make my own wheat paste.
The choice is yours.