The Prophet (ﷺ) said: After wudu, do it properly. Then say this -
أَشْهَدُ أَنْ لَا إِلَهَ إِلَّا اللَّهُ وَحْدَهُ لَا شَرِيْكَ لَهُ وَأَشْهَدُ أَنَّ مُحَمَّدًا عَبْدُهُ وَرَسُوْلُهُ
Transliteration
Ash-hadu an laa ilaaha ill-Allahu wahdahu laa sharika lahu, wa ash hadu anna Muhammadan ‘abduhu wa Rasooluhu
Translation
I bear witness that none has the right to be worshipped but Allah alone, Who has no partner; and I bear witness that Muhammad (ﷺ) is His slave and His Messenger.
Note
The eight gates of Paradise will be opened for him; He will enter (Paradise) through whichever door he wishes.
Say this after wudu. Paradise's eight gates open for you. The Prophet Muhammad promised it. Pick any gate you want - walk into Jannah.
The Shahada is best: Ash-hadu an la ilaha ill-Allahu wahdahu la sharika lahu. Authentic hadith. Huge reward waiting.
The Prophet said it clearly: Jannah's eight gates open. You pick which one to enter.
Yes. After ablution, you say Kalima Shahadat. You declare: no God but Allah. Muhammad is His Messenger.
Yes. Feet washed? Last step done? Step away from water. Say it immediately.
Some people look up. But the hadith focuses on the words. Say them with your heart - meaning matters most.
The hadith says 'does it well'. Try to do wudu correctly, following sunnah. Then say the dua.
Yes, 'Allahummaj 'alni minat-tawwabina' is sometimes said too. But the one with 8 gates promise is the Shahada.
No, not fard. Not required. It is Sunnah. Big reward if you do it. But your wudu is valid without it.
It is very short. Know Kalima Shahadat? You already know it. Just remember - say it every time you finish washing.
Better to move your lips. Say it softly - you can hear yourself. But don't say it loud if toilet is nearby.