So I started a mood calendar on Jan 1st, and I have successfully kept it for about two weeks! (Doesnt sound like much but I usually give up on these things after a couple days lmao)
I have a color key in front where each color represents a different emotion that I think best describes how I was generally feeling for the day, and I paint over each day accordingly. Then I have two lines of paper to write a little blurb about how I was feeling and why (limited space so I don't dwell on the bad) 

These are the things I've already found it helping me with, in case you struggle with them too!:
-Black + White thinking: when I'm having a not so great day, it can help to see all the days when I felt Loved, Hopeful, Accomplished, etc. to remind me that no. Not every day is terrible. It just hurts right now. 
-Patterns! Sometimes it feels my emotions are just kinda randomly generated but I've noticed some small pattern behavior and it's good to recognize those, good or bad. 
-Shitty short-term memory: the writing part REALLY helps my memory, I often get days mixed up, struggle with chronologizing things that have happened in recent weeks-months. Super helpful there. 
-Coping skill alert! Helps me S.T.A.R throughout the day! STOP, THINK, AND REACT. "How am I feeling right now and am I going to let it ruin the mood of my whole day? I don't want to have to color my day in black (out of control), let me get control of myself right now."

Anyway, sorry for the long post, I hope someone can be helped by this!!! Much love, stay happy + stay weird!!!