After Tasleem Dua

What to say immediately after final Tasleem (Assalaamu Alaikum Warahmatullah) in salaat. BismilLaahir Rahmaanir Raheem.

These are all recommended Sunnah of the Prophet PBUH. It's not compulsory but highly recommended acts of worship to keep us connected to Allah.

1. First ask forgiveness by saying: "ASTAGHFIRULLAAH" 3 times. 2. Then we should add;
"ALLAHUMMA ANTAS SALAAM, WA MINKAS SALAAM, TABAARAKTA YAA ZAL JALAALI WAL IKRAAM. ""O Allah, You are the source of peace and from You comes peace, exalted You are, O Lord of Majesty and Honor."
3. It is also recommended for the worshipper to recite thereafter the following supplication: "LAA ILAHA ILAL-LAHU WAHDAHU, LAA SHARIKA LAHU, LAHUL-MULKU, WALAHUL-HAMDU, WAHUWA ALAA KULI SHEY-IN QADIIR" "None worth worship except Allah, He is one, He has no partner, to Him belongs sovereignty and to Him belongs praise and has power over all things".
4. And says thereafter: 
"LAA HAWLA WALAA QUWATA ILLA BILLAAH""There is no might or power, except from Allah".
5. Then "ALLAHUMMA A'INNII 'ALAA ZIKRIKA, WA SHUKRIKA, WA HUSNI IBAADATIK""O Allah, help me in remembering You, thanking You and conducting my worship to You in a perfect way".
6. Then we should recite these zikir; a) SUBHAANALLAH. Glory be to ALLAH - (33 times). b) AL HAMDU-LILLAH. Praise be to Allah - (33 times)
c) ALLAHU AKBAR (33 times).
Then, at the end of the above three recitations, the worshipper recites the following supplication:"LAA ILLAHA ILAL LAAHU WAHDAHU LAA SHARIKA LAHU, LAHUL MUL-KU, WALA-HUL HAMDU, WAHUWA ALAA KULI SHEY'INN QADIIR""There is no god but Allah alone, He has no partners, to Him belongs dominion and to Him belongs praises, and He has power over all things".
By this supplication, the worshipper makes up a total of 100 readings. In this regard, it was reported in an authentic prophetic saying that whoever comes up with this 100 phrases at the end of every obligatory prayer: “Allah will forgive him, even if his/her sins were as abundant as the foam of the sea”(Reported by Imam Muslim). ALLAHU AKBAR.

From the above we should recite Aayatul Kursy,  then the last suurahs of the Quran Ikhlas,  Falaq and An-Nas to seek protect from Allah then you can add your personal dua request including me😊. May Allah accept our salaat,  dua and forgive our sins. Aameen.