If you knock a door or ring the bell when you visit someone, and are asked "Who is it?" you should identify yourself by giving your common name or kunya. It is disliked to respond "It is me" or "Somebody" or "Guess who?" because these do not give away your identity and may agrevate the person being visited who may indeed not recognise voices easily.
Jabir Ibn Abdullah (رضى الله عنه) narrated: "I went to the Prophet (صلى الله عليه وسلم) for a debt that was upon my father. I knocked on the door, and He (صلى الله عليه وسلم) said, "Who is there?" I answered "Me". He said "Me, me" in a way that showed His dislike of my answer.
(Bukhari & Muslim)
During the year of the Makkan conquest, Umm Haanai رضى الله عنها (the sister of Ali ibn Abi Talib) once went to the Prophet (صلى الله عليه وسلم) and learned that he was taking a bath. His daughter Fatimah رضى الله عنها was holding up a cover to protect him from the view of others. Umm Haanai later said, "Then I extended greetings of peace to Him, and He said, 'Who is this?' I said, Umm Haanai Bint Abu Taalib..."
(Bukhari and Muslim)
Abdullahi ibn Buraidah (رضى الله عنه) related that his father said, "The Prophet (صلى الله عليه وسلم) left to go to the Masjid; meanwhile Abu Moosa was reciting. He (صلى الله عليه وسلم) said, "Who is this?" I said, 'I am Buraidah; may I be made ransom for you', He (صلى الله عليه وسلم) said 'This one has been given the flute (i.e. his voice) from the flutes of Dawood's family".
(Al Adab Al Mufrad)
Abu Dharr (رضى الله عنه) said "One night while I was walking I saw the Messenger of Allah (صلى الله عليه وسلم) walking by himself. I walked behind him in the shade of the moon, but he turned around and saw me and asked, "Who is there?" I replied, "It is Abu Dharr".
So the correct adab of identifying oneself is to avoid confusion and clearly convey ones identity.