Supplication when slaughtering or offering a sacrifice:
بِسْمِ اللهِ واللهُ أَكْبَرُ اللَّهُمَّ مِنْكَ ولَكَ اللَّهُمَّ تَقَبَّلْ مِنِّي
“In the name of Allah, and Allah is the greatest. O Allah, (it is) from You and belongs to You, O Allah, accept this from me.”