Found this amazing design by davinci85, thought i would utilize his design.
If you are like me, i always charge my phone next to my bed, half of the time i either find the cable on the floor, or worse.. at the back of the nightstand...@(*%$&

Here are some background information.

Cable: Factory Nexus 5x/6p cable(4 mm diameter)
magnet: 3 x 10 mm disk neodymium
scaling calculation: ((4+1.5)-(3+1.5))/((3+1.5))+1 = 1.2222

Since the original from davinci85 was for lightning cable(3 mm diameter), i had to scale it by 1.2222 to make it fit on the nexus cable(1.5 mm was the clearance in the original design).

Now just glue a piece of magnet on your nightstand/headboard to hold your charger cable.

Let me know if you want me to update for different cable diameter or magnet sizes, i will try to upload them.