The three methods of representation are
Electoral Method: Persons are directly or indirectly elected by the citizens to govern them as members of representative assemblies e.g., General elections to Lok Sabha and Legislative Assemblies.
Non-electoral Method: Representatives occupy their position through nomination or appointment for e.g., the President of India appoints 12 members to the Rajya Sabha.
Non-official Method: Civil society represents the people through various pressure groups like trade unions, student groups, etc.