"The Messenger of Allah ﷺ used to say the salam to his right so that the whiteness of his cheek could be seen, and to his left so that the whiteness of his cheek could be seen." (Using translation from Nasāʾī 1323)
كَانَ رَسُولُ اللهِ ﷺ «يُسَلِّمُ عَنْ يَمِينِهِ حَتَّى يَبْدُوَ بَيَاضَ خَدِّهِ وَعَنْ يَسَارِهِ حَتَّى يَبْدُوَ بَيَاضَ خَدِّهِ»