The Prophet (SWAS) and his companions used to sacrifice the camel with its left leg tied and it remained standing on the rest of his legs.  

أَنَّ النَّبِيَّ ﷺ وَأَصْحَابَهُ كَانُوا يَنْحَرُونَ الْبَدَنَةَ مَعْقُولَةَ الْيُسْرَى قَائِمَةً عَلَى مَا بَقِيَ مِنْ قَوَائِمِهَا  

I was present with Ibn ʿUmar at Minah. He passed a man who was sacrificing his camel while it was sitting. He said make it stand and tie its leg ; thus follow the practice (sunnah) of Muhammad (SWAS).  

ابْعَثْهَا قِيَامًا مُقَيَّدَةً سُنَّةَ مُحَمَّدٍ ﷺ  

The Messenger of Allah (SWAS) commanded me to take charge of (his) sacrificial camels and to distribute the skins and saddle clothes (after sacrifice) as sadaqah. He commanded me not to give anything from it to the butcher. He said we used to give it (the wages) to the butcher ourselves.  

أَمَرَنِي رَسُولُ اللَّهِ ﷺ أَنْ أَقُومَ عَلَى بُدْنِهِ وَأَقْسِمَ جُلُودَهَا وَجِلاَلَهَا وَأَمَرَنِي أَنْ لاَ أُعْطِيَ الْجَزَّارَ مِنْهَا شَيْئًا وَقَالَ نَحْنُ نُعْطِيهِ مِنْ عِنْدِنَا