There's a big difference between a simple signature and an advanced signature.
This signature is very fast to set, however the legal validity in these cases is not reassured since the signer only needs to accept the terms and conditions by clicking a button. The signer will not use his own personal signature to sign the document.
Feel free to follow this link to know in detail how to send a document using the simple signature.
This process is more secure than the Simple Signature and demands further steps to reassure the identity of the signer. The signer needs to properly sign the document with his personal signature, with his/her finger or with a touch pen on a smartphone or tablet (recommended), or with the mouse on a laptop or desktop computer.
The audit trail in this case records biometric information like position, speed, acceleration and pressure. Of course, all these advanced features have more legal validity than just accepting the terms and conditions from the simple signature.
Feel free to follow this link to know in detail how to send a document using the advanced signature.