Dua And Dhikr After Salat

Recite: Astaghfirullah 3 times.

Then recite:

Allahumma entas salamu we minkes selam tabarakte ya zel djalali wel ikram.

Then read this:

Subhanallahi wel hamdulillahi we le ilehe ill allahu wallahu ekber,wela hawle wela kuwwete illa billahil aleyyil azim.

Then read Ayatul Kursi.

Then say 33 x Subhanallah, 33 x Alhamdulilah 33 x Allahu Ekber.

Then recite :

Allahu Ekber, La ileha illallahu wahdehu laa sherikah leh , lehul mulku we lehul hamdu we huwa ala kulli shay'in qadir.

Then say :

Subhane rabbiyal aliyyil alal wahhaab, 

Then raise hands with your palms upwards and start your supplication.

You can read any duaa from quran or ahadeeth or formulate your own duaa in your own language.