I keep a text log and add entries manually every morning. I add my best guesses for when I actually fell asleep and when I woke up. I also log when I woke up in the middle of the night and for how long.
For just knowing roughly how long I'm sleeping each night (and how consistent my bed and wake times are), my text log has been good enough.
I'm not even sure I should be keeping track at all. As the article points out, it may exacerbate sleeping problems by causing me to worry too much about sleep in the first place.
I'm interested in using a device, but I'm skeptical of the accuracy for data like how long my REM cycle were: https://www.menshealth.com/health/a26932734/sleep-trackers-a...
For just knowing roughly how long I'm sleeping each night (and how consistent my bed and wake times are), my text log has been good enough.
I'm not even sure I should be keeping track at all. As the article points out, it may exacerbate sleeping problems by causing me to worry too much about sleep in the first place.