Actions requiring partner/account authentication will need your Partner Id, your Partner Token, and the Account Token for the account you wish to access. These values must be concatenated together seperated by a ":" in the format "PartnerId:PartnerToken:AccountToken" and then must be BASE64 encoded. The partner credentials supplied may be for either the credentials for the partner the account was created under or for the direct parent of that partner if applicable.
Given the partner token "pppppppppppppppppppppppppppppp" and the partner id "00000000-0000-0000-0000-000000000000" the account token "aaaaaaaaAaaaaaaa" the concatentated string would be "00000000-0000-0000-0000-000000000000:pppppppppppppppppppppppppppppp:aaaaaaaaAaaaaaaa". Then that string must be encoded into BASE64, in this case resulting in "MDAwMDAwMDAtMDAwMC0wMDAwLTAwMDAtMDAwMDAwMDAwMDAwOnBwcHBwcHBwcHBwcHBwcHBwcHBwcHBwcHBwcHBwcDphYWFhYWFhYUFhYWFhYWFh". This BASE64 encoded value must be passed in the request as the value of the PartnerAuth parameter.