Hygrometer question

I just bought digital thermometer/hygrometer from Walmart. It is a national Geographic one that was about $20. They didn't have the accurite brand here in Canada. I am just using it for humidity readings as I have two pretty accurate thermometers.

My question is where do I place the unit to read. I have in up a couple inches in the middle of the cage. Should it be middle or cool side or hot side? Should it be right on the floor or up a couple inches?

The readings will be different on the hot side and cool side. The heat lamp will lower the humidity on the hot side. I place my hydrometers on the cool side so I can see the highest humidity level in the cage.

Thanks! I am going to measure for 24 hours and then go and get some substrate. I am getting anxious to get a snake and my wife and I are going this week to look. I want to get everything up and running though first.