Muhammad ibn Ishaq said: I saw as-Salt ibn Abdullah ibn Nawfal ibn Abdul Muttalib wearing the signet-ring on his right small finger. I asked: What is this? He replied: I saw Ibn Abbas wearing his ring in this manner. He put its stone towards the upper part of his palm. Ibn Abbas also mentioned that the Messenger of Allah ﷺ used to wear his signet-ring in his manner.
Related hadith on this topic
Explanation & Benefits
Shaykh Umar Farooq Saeedi
Benefits and Issues:
It is recommended (mustahabb) and Sunnah that the ring be worn on the little finger of the right hand.
Source: Sunan Abu Dawood – Commentary by Shaykh Umar Farooq Saeedi, Page: 4229