The Prophet ﷺ sacrificed two horned, white rams. He slaughtered them, said the takbir, mentioned Allah's name, and placed his foot on their sides.
حدثنا مسلم بن إبراهيم حدثنا هشام عن قتادة
أن النبي ﷺ ضحى بكبشين أقرنين أملحين يذبح ويكبر ويسمي ويضع رجله على صفحتهما
Sourced by Bukhari, in the chapter on asking by the names of Allah Most High and seeking refuge by them, in the Book of Tawheed, hadith no. 7399, from the hadith of Hisham Dastawai, with the same account.