How to add Customer Sign on PDF and Save in database

Hi This is Shivaraj.

I Have Making Editable PDF, here i required customer sign on pdf   (example- draw customer sign on my pdf  and save in the database )

• how can i add there customer sign( draw sign )
• which feild is need to Take ?
• how i have to save customer sign feild in the database 

 I attached my template as bellow image

so please suggest me, i hope you will understand my proble .