Capturing customer signature on mobile app — which fields?

hey so basically im trying to figure out how to get customers to sign off on jobs when im out in the field and i found the signature thing in the app but like im not totally sure which fields i need to set up or if theres something in the web side i gotta configure first? my dispatcher mentioned something about form templates but honestly i wasnt really listening lol anyway i tried just tapping around and i see "add signature" but it says no signature fields configured or something like that so yeah what am i missing here