Best place for motion sensor

[JDRoberts]

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Placing sensors

I am just starting my install and was wondering if anyone had any tips on placement of motion sensors specifically to trigger lights when entering a room. I have two doors on either wall of a corner, one is a bedroom and the other the washroom. I initially thought I could a sensor on the ceiling above each door, but I believe they would both trigger regardless which room I was entering. For the bedroom I only want it to trigger when entering, not for all movement. The door is open so I can’t choose a door sensor. The bathroom I’ll have on a 5 minute timer, but I still don’t want to trip it when I’m walking into the bedroom. Any ideas or suggestion are welcome. Thank you.