Answer

It is a sunnah of the Prophet of Allah Sallallahu Alahi Wasalam to make dua after Salah. It is a time when ones dua is accepted. In order for our dua to be accepted by Allah (SWA) it is important that we keep in mind some etiquettes of dua.

It is preferable and desirable to make dua quietly however, if there is a need to teach people the relevant duas then it will be permissible to say it loudly. (Fathul Baree p.269 v.2)
It is desirable to read duruud shareef at the beginning and ending of the dua. (Aapke Masaail p.283 v.3)
It is a sunnah of the Prophet of Allah Sallallahu Alahi Wasalam to raise your hands in dua. (Fatawa Mahmoodiyah p.241 v.10)
One should raise his hands to his chest and it is preferable that there is a small gap between the hands. (Fatawa Rahimiyah p.304 v.4)
If one is doing dua behind the Imam it is desirable to say Ameen after each dua. (Fatawa Mahmoodiyah p.261 v.10)

Only Allah Knows Best

Mohammed Tosir Miah

Darul Ifta Birmingham