Members of the House of Lords are appointed by the Queen on the advice of the Prime Minister. Some non-party-political members are recommended by an independent body, the House of Lords Appointments Commission.
Fun Fact!
54 of the 793 Lords are on Leave of absence (Taking a holiday from being a Lord). 8 of those have been disqualified because they are Judges, and 5 of them Hereditary (They inherited their seat from one of their parents.) Of the Lords still in their seats, 90 of them are Hereditary.