Any way to start and stop sleep manually

With my 920XT I liked the accuracy of being able to start and stop the sleep tracking manually.

Is there any trick to doing that with the Fenix 5X? Is there something I did not catch in the directions?

The automatic has not been very accurate for me - example is that it said I went to bed last night at 9:58 but actually went to bed at 12:20, it did get my wake up right this morning.