What is the correct way of performing Wit'r prayer of 3 Raka'ats?

The way I pray wit'r prayer has come to my knowledge to be wrong as I pray it exactly like the fard prayer of Maghrib (which the Prophet Muhammad (SAW) has told us not to do). So I have looked up the internet and found two ways of doing it correctly. But I do not know which one is the best and most accurate way. **What manner should the Wit'r prayer be prayed in:** 2 Rak'ah - (Tasleem) - 1 Rak'ah or 2 Rak'ah - (without sitting + no tasleem) - 1 Rak'ah? *Jazak Allahu Khayran.*