Or have ADHD, You'll be all over the place every 5 minutes.

This is what I did this year and last one too.

I started tracking my spending to see where my money was going which was very insightful. Patterns emerged I never could have seen if it wasn’t all laid out in one spreadsheet.

For instance, I learned based on a little experimentation that driving 65 instead of 75 on the highway saved me like $50/month. Yeah, I’m that guy and my commute takes another couple minutes but I still do this today. I’ve reframed it in my head as a $50/mo subscription that doesn’t give me much value for the money and only costs an extra few minutes a day. Worth it in this inflation era.

Also realized I was spending money in all these categories that I could be getting some high cash back credit cards for. When you can see your spending averages over time, it’s easy to be confident about getting a strategic 5% card for gas or online shopping that can claw back a decent chunk of the money you already know you’re gonna spend.

It’s definitely useful to track your spending, in more ways than one

I imagine it would be useful as a learning experience, even if that level of tracking didn't go on forever.

I'm thinking of how tracking calories feels analogous; the time I spent dedicatedly tracking the calories of my food consumption was super helpful in recalibrating my intuitive understanding.

The first few months were a lot of effort because I had to do stuff like putting a bowl on a weighing scale and add what I considered to be an appropriate amount of cereal, and working out how many calories were in that, then doing similar for the milk. It was shocking to see how many calories were in some of the typical things I ate, but beginning to be honest about that and logging my reality was necessary to starting making positive changes. Because I tend to slip into disordered eating when I try to lose weight via calorie counting, I've found that I need to take a more freestyle approach and go for more qualitative goals like "eat more veg", "cook more meals", "drink glass of water before snacking" — goals that can be specific and towards being healthier, but don't require too much number crunching. However, I wouldn't have made as much progress without having spent a decent amount of time tracking things, judgement free.

The judgement free part is the hardest part, and I imagine that applies for tracking spending too. Did you ever have instances where you saw how much you were spending on a particular thing and cringed so hard that you found it harder to be truthful in your tracking? I know that I struggle with guilt a lot, and that can make it easier to put my head in the sand.

Yes, track the dollars even if the outflow is greater than the inflow. Then you will at least have an idea of where to start

Also, generally avoid alcohol consumption. It's weird that this drink, when consumed regularly, has the ability to hijack and reprogram your biology so much that stopping can kill you. Just best to avoid it.

This is very important. It's easier to do regular "exercise" if it's part of your daily routine than having to go out of your way to go to the gym.

The fittest I've been on the last years has been when I could bike to the office

That's it! Walking solves so many problems automatically, it's possibly the best general answer.