A few things I've noticed about personal essay writing, after reading too many and attempting a few:
The best personal essays aren't really about the writer. They use the writer's life as a lens for looking at something larger. James Baldwin's "Notes of a Native Son" is about his father's funeral. But it's also about the Harlem riots, and underneath both of those, it's about what it means to inherit rage. The personal part is the entry point. The room is always bigger.
Readers trust specificity. "I was sad" does almost nothing. "I sat in the parking lot of a Walgreens for forty minutes because I couldn't figure out which door to walk through" does a lot. The concrete detail is where the feeling lives.
Most first drafts of personal essays are the writer figuring out what they think. The second draft is where you write it for someone else. Those are two completely different documents wearing the same title.
Claudia Rankine's Citizen: An American Lyric uses "you" instead of "I." It puts the reader inside the experience rather than asking them to watch from outside. It shouldn't work. It's disorienting. But that disorientation is the point, and I think about it every time I'm deciding which pronoun to start with.
If you're writing a personal essay and you know exactly what you think about the subject before you start, the essay is probably going to feel flat. The best ones have a quality of the writer thinking on the page, working something out in real time, following a thread they can't quite see the end of yet.
Truman Capote's "A Christmas Memory" is technically about making fruitcakes with his elderly cousin. What it's actually about is the last year of a relationship before the world pulled two people apart. He never says this directly. He trusts the fruitcakes and the kite-flying to carry the weight. That restraint is the whole essay.
Ending a personal essay is harder than ending almost any other kind of writing.
I'm not sure why so many personal essays work better when they circle back to an image from the beginning rather than arriving at a clean conclusion. Maybe it's because real life doesn't conclude. It repeats, with small variations. The circular structure feels more honest than the linear one.
Ta-Nehisi Coates wrote Between the World and Me as a letter to his teenage son. The form gave him permission to be direct in a way that a traditional essay might not have. When you're writing to one person, you stop hedging. You stop qualifying every sentence for an imagined critic, and you just say what you mean.
The best personal essays tend to have a single controlling image, one physical thing that keeps returning. A house. A pair of shoes somebody left by the door. The image does the structural work that a thesis statement does in an academic paper, but it does it without the reader feeling managed.