I found the best way to mount my hue sensors is in the ceiling corners, but the included screws and magnet do not make this possible, so I made this minimalist and elegant mount which makes it easy to mount the sensor in the corner of the ceiling at 45° horizontally and 30° vertically using only the included screws and magnet. I recommend printing with the seams on the back for a near-perfect finish.
For tricky corners where there's small gap between the sides and the ceiling, I made an adapter that snaps right onto the mount: https://makerworld.com/en/models/139504#profileId-152029
Want to mount the sensor in the ceiling, but not in a corner? Check out my compact ceiling mount here: https://makerworld.com/en/models/194596#profileId-215065
Video, more info and other smart home projects on my FB page “Rune's smart home blog” and my YouTube channel “DIY techie”.