This might look like a bread board with the glass from an old picture frame taped to it, and... well that's what it is. I've folded a few paper towels and put them behind the board to make sure the pressure is evenly distributed across its surface. It's very important for the result of the exposure that there is no distance between the layer of photoresist on the board and the negative film.
I use the timer in the mobile phone to keep track of the exposure.
