This document provides an overview of common sales mistakes and how to improve sales skills. It discusses 13 key skills and traits that are important for sales success: readiness, knowledge, rapport, prospecting, qualifying, presenting, closing, objections, customer service, administration, attitude, drive, and influencing. Some common mistakes include lack of readiness, knowledge, or proper rapport building skills among salespeople. High or low scores on these traits can also indicate issues. Regular skills assessment, training, and support can help salespeople improve.