Sayyiduna ‘Umar bin Khattaab (radhiyallahu ‘anhu) reports that Rasulullah (sallallahu ‘alaihi wasallam) said, “Whoever performs a perfect wudhu and thereafter recites the following du‘aa, eight doors of Jannah will open for him, and he may enter from whichever door he wishes:
أَشْهَدُ أَنْ لَّا إِلَهَ إِلَّا اللهُ وَحْدَهُ لَا شَرِيْكَ لَهُ وَأَشْهَدُ أَنَّ مُحَمَّدًا عَبْدُهُ وَرَسُوْلُهُ اَللَّهُمَّ اجْعَلْنِيْ مِنَ التَّوَابِيْنَ وَاجْعَلْنِيْ مِنَ الْمُتَطَهِّرِيْنَ
I testify that there is no deity besides Allah, who is alone, without any partner, and I testify that Muhammad (sallallahu ‘alaihi wasallam) is His servant and messenger. O Allah! Make me from among those who constantly repent, and make me from among those who are pure!” (Sunan Tirmizi #55)
In the above hadeeth, Rasulullah (sallallahu ‘alaihi wasallam) has prescribed an extremely easy action which will assist us to enter Jannah. As each of us has to perform wudhu at least several times daily before we perform salaah, all we have to do is ensure that we recite the above-mentioned du‘aa on completing our wudhu to qualify for the glad tidings.
However, Rasulullah (sallallahu ‘alaihi wasallam) also mentioned that one should try to perform a ‘perfect wudhu’. In order to achieve this, one should adhere to all the etiquettes and sunnah and mustahab actions of wudhu, such as facing the qiblah, washing each limb thrice (besides masah of the head which is only once), not wasting water, cleansing the mouth with the miswaak, refraining from any worldly talk, etc.
May Allah Ta‘ala bless us all to qualify for these glad tidings.