A sleep tracker. The worst thing about sleeplessness is the fear of sleeplessness. Once i saw that my sleep wasn't anywhere near as bad as it felt, it helped me a lot to cope with it.
I use google sheets and just made a sleep tracker, initially matching the sleep log my specialist had me do on paper for ages. Does excel have like a template or something? Mine is a chart of time stamps and values I have it automatically calculate, with checkboxes for goals and whatnot. At some point it'd like it to graph it so I can see sleep phase/timing but currently it works okay for my needs with the values I have it calculate
It'll be reaaaaally hard for me to make it graph since time is circle/spiral and the style graph/chart I like requires breaking that circle each day, but my sleep timing changes over time... But I still want it to, itd be so pretty! 🥹
edit: I found this pic of someone's setup with the style graph I like! :)