How to become a good mechanical designer:
1. Solid basic knowledge and theoretical knowledge, master mechanical principles, interchangeability, tolerance fit, theoretical mechanics, technology and other knowledge.
2. Proficient in using AUTO CAD, UG, pro E and other software, with corresponding knowledge, skills and drawing ability.
3. Form concepts, meet the characteristics of good processability, and understand knowledge beyond various designs.
https://www.youtube.com/watch?v=6VDj9x2rLRE
mechanical principles examples
First of all, first: need to have mechanical principles, mechanical design, mechanism, material technology, mechanical manufacturing and other aspects of knowledge. Second, as a mechanical engineer, you need to develop your spatial imagination.