I decided that the wallpaper should be dark blue, and I used ordinary coloured printer paper which I splashed with gold paint. For the ceiling I used a bit of blue corrugated cardboard I happened to have, possibly a wine-bottle case. I made flagstone floor like the one I have in my Victorian kitchen only I cheated this time. I rolled out a bit of clay large enough to cover the floor and made patterns on it with a pencil.
I made a book case just like the one I have in my Victorian house, and I made a low table to put all Lord Asriel's instruments on. I wanted telescopes that could move, and I used cufflinks to make them. I used all kinds of springs and cogs and wires and weird-looking metal things and bottles. I made a standard lamp using a mini candlestick, a bit of a fluid soap pump and a brass button on top. I made a little table to hold the Golden Compass which I made from a schampoo cap and a hand from a broken clock. I painted magical signs on the compass with a golden pen. I changed fabric on the chair using a bit of a leather purse. I cut the map from a catalogue and made a frame from grill sticks. The Persian rug is cut from a pencil case. I used drinking straws for pipes. I don't remember how I came up with this idea, but it became an interesting feature.
Of course I had to fill the book case with books. Since I don't print out anything from the web I had to use whatever I found in catalogues that would fit in Lord Asriel's library and that would be meaningful for me and my son. So apart from the obvious Oxford English dictionary I found titles such as The Secret of Life, Antimatter and How Professors Think.
This is the final view of the room before I sent it away to Sweden, carefully packed in my husband's car.The strange object in the left bottom corner is a bit of a broken latte whisk.