You could put a number on the skills to structure your answer around this. For example, "In my opinion, the three most important sales skills are…" Instead of referring to specific sales techniques, you should mention competencies and skills which a salesperson need to get success. Below are some skills including:

► Adjust your approach to different people and situations.

► Ask a right question and how to listen.

► How to communicate and handle dissatisfaction and rejection of customers.

► Make plan and comply with it.

► Make influence on and persuade customers.

► To be good at negotiating for common agreement.