Behavioral Finance(must read the book)

Must read the book first!! This letter must based on the knowledge from the book!!
Imagine that you are a financial advisor and a client has come to meet with you to review his portfolios performance over the last year.
While the returns of the clients portfolio have matched the market and he is invested in accordance with his risk tolerance, he has heard that some of his friends last year have achieved above market returns due to choosing individual stocks or fund managers and he is upset with you that he has not achieved the same above market returns.
He has heard that the 30-year rolling average for the S&P 500 is 10% and believes his portfolio should achieve that or higher each year.
The client has 50% of his portfolio in his own tech companys stock, and he is extremely hesitant to diversify.
During the meeting you see the client constantly checking his phone to look at stock prices. 
Additionally, the client is seriously considering quitting his job with the larger company, withdrawing 50% of the diversified portfolio he has with you, and using his time, money, and effort to start a brand-new software business.
Based on what you have learned from the book, write a 1,000-word letter to the client advising him on how he should think about his portfolio, what to do with his concentrated stock, how often he should check his stock prices, and whether or not to quit his job and start a new company. 
As the client has not read the book, some summary will be required, but better papers will focus on application of concepts in the book to the client’s situation and use the concepts to provide advice to the client.
Please put concepts in your own words that your client would understand and try to avoid quoting the book at length.