Bismillahir Rahmaanir Raheem
1. To leave the Masjid with
the left foot.
(Bukhari-Chapter on Salaah pg. 61)
2. To recite 
(Ibne Majah pg. 56)
3. To
recite Durood Sharief e.g.
(Ibne Majah, Faydhul Qadeer Vol. 1, pg. 336)
4. To
recite the Dua:
(Ibne Majah)
From "BEAUTIFUL SUNNATS OF THE BELOVED
NABI (SALLALLAAHU 'ALAYHI WASALLAM)
By Hadhrat Moulana Shah Hakeem Muhammad Akhtar Saheb
(Rahmatullahi 'alayh)
Download the book here