Finance
Money is a rate problem, not an amount problem.
Nobody fails at money because they cannot do arithmetic. They fail because every decision is made once, under pressure, by a tired person. Move the decisions out of the moment.
Going deeper
Everything above works. This is what it does not cover.
Written mechanisms are good at explaining what to do and poor at showing what it looks like when it goes wrong. The finance lessons are filmed on real cases, including the ones that do not resolve neatly.
Coaching exists for the part no article reaches: your constraints, your week, and the specific thing that keeps breaking after the third attempt.