All former and current Presidents are referred to as "His/Her Excellency" for life.
All former and current members of a Presidential cabinet are referred to as "Minister" for life and/or can end their name with the suffix "MPC" for "Member of the Presidential Cabinet".
All current and former Senators are referred to as "Lord" or "Lady" for life. All current and former Representatives are referred to as "Sir" or "Dame" for life and/or end their name with the suffix "MC" for "Member of Congress."
None of the above titles are passed on to children, etc.
Those who are awarded military medals for valor may use a suffix at the end of their name:
Medal of Honor: MOH
Distinguished Service Cross: DSC
Silver Star: SS
Bronze Star: BZS (unless you want BS at the end of your name!)
Purple Heart (PH), etc.
Civillian orders can include something like this:
Order of the Columbia: For outstanding services to the Federal Government, recommended to and selected by the President. Those awarded can end their name with the suffix "OC"
Order of America: For outstanding volunteer services in the United States. People are nominated on a yearly basis to a committee who select the most worthy candidates and are reccomended to the President for approval. Those awarded can end their name with the suffix "OA."
Order of the State of ---: For outstanding service to the government of a particular state (or at the local government level). Recommended by the Governor of that state to the President for approval. Those awarded can end their name with the suffix "OS"
So, a President who once was a member of Congress and won medals in the military would have something like these:
His Excellency, Sir John Doe, DSC
His Excellency John Doe, MC DSC