A. Jefferson recommends you use a combination of numbers and letters (UPPER CASE and lower case) and also a special character ! @ / # * ? & .
Change your password at least every three months. Never disclose or make obvious your password to any third party. Never write down or email your password.
Never use your name, spouses name, children's names, house names or anything that obviously is connected with you and in the public domain, e.g., your work title, make of car, home town, etc.
NOTE: Jefferson will never ask you to disclose your password to them.