# Signing a document

This feature allows you to digitally sign your documents with electronic certificates.
Before starting, you might find interesting looking at the following pages:

- [How to configure a Digital DNA key](/products/namirialsign/mobile/userguide/ddna)
- [How to configure a Remote signature](/products/namirialsign/mobile/userguide/remotesignconfig)
- [How to configure a Graphic signature](/products/namirialsign/mobile/userguide/settings)
- [How to configure a Timestamp](/products/namirialsign/mobile/userguide/timestampconfig)


You can start the signing operation in one of the following ways:

- By tapping the "Sign" button in the top menu of the Home screen.
- By entering in the "History" section, tapping on the signed document and selecting "Add signature".
- By sharing the document available on the smartphone with Namirial Sign app and selecting "Sign".


Sign - file selection
## Configurations

Once the file has been selected, the configuration screen will appear.

Sign - configurations
Here there are four main settings:

1. Identity selected for signature: here you can select which certificate is to be used, remote and local certificates are identified with a different icon.


Sign - select certificates
1. Signature format: here you can choose the type of signature you want to perform, the options are PAdES, CAdES, and XAdES.


| **Extension** | **Description** |
|  --- | --- |
| **PAdES** | Can be applied to files with .pdf extension, generating a signed .pdf file. |
| **CAdES** | Can be applied to files of any extension, generating a signed .p7m file. |
| **XAdES** | Can be applied to files of any extension, generating a signed .xml file. |


1. Enable graphic signature: this is available only for PAdES signatures, it allows you to add a graphic signature to the document.
2. Timestamp: here you can choose whether or not add a timestamp to the signature.


In case you have not configured any certificate or timestamp, you can do that in this phase.

Sign - configurations with no certificates and timestamps
## Preview and graphic signature

After completing the configurations, you will see the preview of the file, in case you have enabled the graphic signature, you will be able to place it. Just select the page and place the signature where you prefer.

Sign - graphic signature
## PIN and OTP

After the preview, you will be asked for the PIN and the OTP according to the certificate you have choosen.

### DigitlaDNA key

In case of a DigitalDNA key, only the PIN is needed.

Sign - PIN for DigitalDNA key
In case you have already saved it under biometrics after the pairing, you will be asked for your fingerprint or face ID according to the device. You can change this configuration even here, by choosing "Touch ID" or "Face ID" the PIN will be saved and you will be no longer require to insert it. "Touch ID/PIN" and "Face ID/PIN" means that you will be asked for both the biometrics and the PIN.

### Remote signature

In case of a remote certificate, you will need the OTP too.

Sign - PIN for remote signature
The remote certificates' PIN can be saved under biometrics too.
Once you have choosen your OTP method and filled the PIN (or used the biometrics), you can confirm and fill in the OTP.

Sign - OTP for remote signature
## The document has been signed

These steps complete the sign operation, you can now share the file or [verify](/products/namirialsign/mobile/userguide/verify) it.

Sign - complete