I import my transactions into Beancount, a plain text accounting software, a few times a year. My setup uses basic machine learning to classify each transaction. This gives me a decent understanding of my situation when combined with Fava, which visualizes the data.

Each month I save a set amount of money automatically into a few different index funds.

I make sure everything that is a monthly payment is something I actually use. Only one streaming service at a time, cheapest phone service etc.

I keep an eye on my main account every now and then to see how much I have. If i feel like it is stacking up more than what I may need in a short amount of time, I either buy more index funds or put it in an account with interest on it. If the main account ever runs out of money I have done something wrong.

I would say I don't really budget. For me I do not feel the need. I am by no means rich, but not spending money on wasteful things really does a lot. E.g. make food most of the time instead of eating out, cut your own hair, only buy things that last and do your research before buying anything significant.

Please keep in mind I live in the EU and pay a sort of salary insurance so I do not have to stress a lot if something were to happen to change my situation.