The quickest way to look confident is not to memorise fifty techniques. It is to understand a small number of principles and apply them consistently.
Start with positioning
If either person is uncomfortable, technique deteriorates quickly. Build the environment first, then the movement.
Pressure is communication
People experience pressure differently. Ask, observe and adjust. Pain is not a badge of effectiveness.
Know when not to massage
Professional competence includes recognising limits. Unexplained pain, acute injury, inflammation or medical concerns can require appropriate healthcare assessment rather than massage.