The fundamentals that make every other money decision easier: how budgeting actually works, how much emergency cover you need, and the common mistakes that quietly cost the most. Worked examples throughout, no jargon.
Read these in order if money management is new: what a budget actually is, then the emergency fund, then the mistakes that quietly cost the most. Each one assumes nothing from the others.
The emergency fund comes before investing, every time. It is what stops a bad month turning into debt, and it is the reason a budget survives contact with reality.
Once the basics are in place, the emergency fund calculator tells you the figure to aim at for your own expenses.
One caution on order: clearing high-interest debt outranks investing, because the guaranteed cost of card interest beats any expected market return. The sequence that holds is emergency fund, then expensive debt, then investing.