You can define header fields in the form of a table containing name/value pairs. This table can be passed to the request object when submitting it. For more information, see Submitting a Request.
The following code snippet defines two header fields (header1=value1 and header2=value2) and appends them to table lt_header.
DATA: ls_header TYPE IF_CLB2_METHOD_GENERIC=>ts_field, lt_header TYPE IF_CLB2_METHOD_GENERIC=>tt_field. ls_header-name = 'header1'. ls_header-value = 'value1'. APPEND ls_header TO lt_header. CLEAR ls_header. ls_header-name = 'header2'. ls_header-value = 'value2'. APPEND ls_header TO lt_header.