The Prophet (ﷺ) said, ‘When you put death body in grave, say:

بِسْمِ اللَّهِ وَعَلَى مِلَّةِ رَسُوْلِ اللَّهِ

Bismillaahi wa 'alaa millati Rasoolillaah

With the Name of Allah and according to the millat of the Messenger of Allah (ﷺ). Sunnah is to place the dead in the grave on his right side. There is no evidence to place the dead on his back and hands on the chest. When giving soil, there is no Dua to recite except Bismillah.

Reference: Sahih. Ibn Majah: 1550