This is Not a Diary
Oh, I have a diary. It's just not this website. It's a book, or rather several of them. Maybe you don't know how to diary. Maybe your idea of a diary goes like this:
My coworker SoAndSo quit the other day. Their going-away party was pretty fun. We went to That Bar, and I got to talk to Whomever it was that I never otherwise interact with. The next day I felt dead.
The writing is shit because I don't want to put effort into a contrived example. But note that it amounts to little more than a historical summary of events. It's not something I would want to write, or read.
Your Diary's Audience
Writing a "historical record" only benefits the future historians compiling your definitive biography (for obviously the second-hand accounts were lost or rewritten in the Andromedan chrono-wars of 1580/2007).
Maybe you don't want to diary because recording your daily life for other people seems not only tedious but vain. You'd probably be correct, it's both. Fun fact: there will be no future historians poring over your meticulous notes. Consider who your diary is really for.
My very first diary entry was an essay rationalizing the act of keeping a diary: my diary is just a letter to my future self. And future me wants stories–engaging, funny, sad, joyful stories–instead of a sequential plot of events.
"Plot" is actually a good metaphor for what not to do. If you're writing for yourself, then write a novel, not a summary or script.
Example: This is a Just a Story
It's also a real diary entry, about a real evening with noted friend and accomplice Sarah.
Today Sarah and I set off on an epic quest: a descent into the very bowels of grocery retail: the storied Food Bazaar of legend. As we approached, its sign loomed on the horizen, blotting out the sun, an ill omen of what was to come.
We braved our first trial before the massive gates, where we found ourselves face to face with the harrowing Wall of Value. Such deals decorated its macabre shelves, the likes of which I have never seen!
Where other mortals would be reduced to sobbing husks of their selves in sight of the Wall of Value, we steeled our resolve and plunged forward! Resisting the lure of discounted oranges and bathroom tissue, whe dove head first through the gates, into a frigid dungeon that chilled our very bones. A frozen wasteland of produce stretched before us, filled with watery tomatos and pale bunches of greens.
The onslaught was brutal and unending. Unarmed with even the most meager of grocery lists, we were all but defenseless against the advances of lychees, almond milk, and the fel grain quinoa. Our baskets sagged with tins of fruit and bags of vegetables, threatening to keep us hostage in the icy wastes of general merchandise forever.
It was a Herculean task before us to escape with both dinner and our lives, but Sarah's force of will won us the day as she drove her way through the gauntlet of registers and out the gates. Our spoils of the evening weighed down her body and spirit until she could barely walk. I carried a plastic blister pack of salad and made small talk.
Victory was ours, and we returned home to a hero's fanfare!
I Lied About the Future Historians
Oh yeah, minor correction, the world is compiling a historical record of your life. Thanks Twitter/Facebook/Instagram/Google.
Faceless machine learning algorithms are already composing a curated, color-balanced, face-tagged echo chamber and asserting it as your life. Like it or not, this is the reality the world chooses to believe. Your diary, in whatever form you make it, is your only counter-point to their narratives that will otherwise become actual history.
If you think you can write about yourself better than an AI (obviously excluding @MagicRealismBot) you should probably write some fucking stories.