Original: The President is elected every five years on May 23 by the Federal Assembly (Bundesversammlung), a special body convened only for this purpose, comprising the entire Bundestag and an equal number of state delegates selected especially for this purpose in proportion to election results for the state diets.
Simplified: The President is elected every 5 years on May 23 by the Federal Assembly (Bundesversammlung). Its members are the entire Bundestag and an equal number of state delegates selected especially for this purpose in proportion to election results for the state parliaments.