mandate = Mollie::Customer::Mandate.create(
  customer_id:       'cst_4qqhO89gsT',
  method:            'directdebit',
  consumer_name:     'John Doe',
  consumer_account:  'NL55INGB0000000000',
  consumer_bic:      'INGBNL2A',
  signature_date:    '2018-05-07',
  mandate_reference: 'YOUR-COMPANY-MD13804'
)