Besides pre announcing your sale, if you are relatively comfortable with the company's future trajectory, you can also consider getting a margin loan backed by

Besides pre announcing your sale, if you are relatively comfortable with the company's future trajectory, you can also consider getting a margin loan backed by the shares rather than selling them. However overall, having substantially all of your net worth and also your paycheck dependent on the performance of your employer is pretty risky and you are likely better off diversifying.