Wazifa details..

Some one gave me this Wazifa last year…i don’t remember who and the other details that follow…but i just seem to remember the wazifa - the person said to read surah yasin 6 times daily…and also recite the durood before and after the prayer…so i was wondering for how many days one must do so? and all…because i’ve heard that if a person doesn’t do the wazifa properly it might turn out to be bad…(is that true?)…and i need to pass on this wazifa to someone else..