You will have to go to the SDM in whose jurisdiction you reside and the typists outside will have the requisite formats of affidavits etc. Finally someone comes to your area to verify after which the SDM issues the certificate.
This is the procedure in Delhi - personal experience.
DISCLAIMER : General information and advice provided is without any warranties as to suitability for any use, correctness and application to any specific case. Please always take proper legal counsel . However, if it helped anyone even a little a " thanks" would be appreciated and would encourage me to keep on making efforts :-) . I am also always open to corrections and further learnings from more experienced Seniors here.