# Submit signature instruction

`POST /devices/{serialNumber}/signature-instructions`

Use this method to submit an instruction to capture a customer's signature on a payment device.  

Our gateway returns information about the signature instruction and a signatureInstructionId, which you need for the following methods:
- [Retrieve signature instruction](https://docs.payroc.com/api/schema/payroc-cloud/signature-instructions/retrieve) - View the details of the signature instruction.
- [Cancel signature instruction](https://docs.payroc.com/api/schema/payroc-cloud/signature-instructions/delete) - Cancel the signature instruction.