I have posted some details about it in other threads. Usually I focus on the bigger picture, therefore the diagramm with my main key performance indicators. I also don't do a detailled cost controlling anymore. I track my expenses in the following categories:
-Housing (25%) (living in my own apartement, rent-free)
-Transportation (16%) (carfree life, 80% by bike + 20% public transportation)
-Food etc. (16%) (almost always cooking for myself and bying wholesale)
-Travel/Leisure (25%) (travel hacking, inexpensive hobbies, e.g. walking, biking, ...)
-Others (18%) (recycling, repairing, DIY, minimalism, simple living)
Overall my expenses are between 7k€ - 10k€ p.a. (average of this and last two years) The numbers behind the categories are the relative share of my total expenses. And I wrote behind the numbers, how I tackle them. (my best practices)