Practise the reasoning, not just the pattern name
Download the two-page workbook, answer the six scenarios, then compare your reasoning with the worked solutions. Topics include interchangeable pricing policies, legal order transitions, monetary precision, optimistic concurrency, simple transition tables, and duplicate-safe event handling.
Each answer explains the invariant and the trade-off. The worksheet intentionally needs no executable code.
Companion learning
Study the free Strategy and State course, then try the related design-decisions mock test.