Capture signature in invoice

Hey all,
I am trying to capture a customer’s signature for an invoice. Preferably, I would like to use the Topaz S460 which I already own. I saw in a previous thread from 2017 this could be achieved using html img tag, but I’m wondering if there is any better way to do it now. Maybe someone has a template I could take a peek at the html behind the scenes? Any tips or guidance is greatly appreciated. (I’m not an expert at html or php but I like to think I can figure this out)

Simplest way is to include a custom field in Invoice with text:

“Please sign the Invoice, here, and signature line:
Signature: __________” (with extra instructions)

Same custom field could instruct customer to print PDF, sign and return scanned document also via E-mail to address you give in same custom field. Anything else is too complicated to do before version 2.