In the past, I've done all sorts of division, taping and remeasuring work out how exactly to hang sets of pictures. After thinking about how negative and positive space are a matter of perception, I realized the solution to this would be to use simple 8th grade algebra.
This technique will save you tons of hassle of measuring, remeasuring, chicken scratch division and putting blue tape all over the place.
* I have no idea what they are doing with the blow-up doll, but all the film stills are equally puzzling and funny.
Step 1: Sketch your space
Draw a simple diagram of the space. Take your time and refer back to this when you are doing the measurements. I drew mine exceedingly quickly. The doorways are the large rectangles that drift into an imaginary floor and the pictures are the tiny squares.