This chapter provides a practical guide for engineering students on mastering essential tools for calculation and documentation. The first section focuses on developing proficiency with scientific calculators, emphasizing the importance of accuracy in high-stakes environments like university exams. It highlights common pitfalls, such as incorrect angle mode settings, and provides a series of reference operations—ranging from basic arithmetic and complex numbers to logarithmic and trigonometric functions—to help users verify their calculator's output. The second section transitions to technical documentation, offering a step-by-step tutorial on using the Microsoft Word Equation Editor. It guides the reader through inserting equation boxes and using specialized ribbons to write professional-grade mathematical formulas, ensuring that complex engineering work is presented clearly and correctly.