You know that advice about drinking eight glasses of water a day? I used to beat myself up about it constantly. Some days I'd realize at 9 PM that I'd had maybe two sips since breakfast, then force myself to chug water before bed—which just meant waking up at 3 AM.
Here's what actually worked: I stopped trying to be perfect and started being practical.
I bought a water bottle I genuinely liked looking at. Sounds silly, but it mattered. Mine has time markers on the side, which helps, but honestly the main thing is that it lives on my desk where I can see it. Out of sight really is out of mind.