✅Answer: Since all the details of Ghusl are not compiled in a single narration, to understand the method of Ghusl, pieces from several narrations will be presented in order, with their chains of narration:

1- Intention (Niyyah):

عَنْ أَبِی حَمْزَةَ عَنْ عَلِیِّ بْنِ الْحُسَیْنِ قَالَ لَا عَمَلَ إِلَّا بِنِیَّةٍ

📚Kafi, Vol. 2, p. 84

Translation: Imam Ali (AS) said: No action is valid without intention.

2- Saying Bismillah (In the name of Allah, the Most Gracious, the Most Merciful):

عَنِ الْعَلَاءِ بْنِ الْفُضَیْلِ عَنْ أَبِی عَبْدِ اللَّهِ قَالَ إِذَا تَوَضَّأَ أَحَدُکُمْ وَ لَمْ یُسَمِّ کَانَ لِلشَّیْطَانِ فِی وُضُوئِهِ شِرْکٌ وَ إِنْ أَکَلَ أَوْ شَرِبَ أَوْ لَبِسَ وَ کُلَّ شَیْ ءٍ صَنَعَهُ یَنْبَغِی لَهُ أَنْ یُسَمِّیَ عَلَیْهِ فَإِنْ لَمْ یَفْعَلْ کَانَ لِلشَّیْطَانِ فِیهِ شِرْکٌ

📚Mahaasin, Vol. 2, p. 430

Translation: Imam Sadiq (AS) said: When one of you performs ablution and does not say Bismillah, Satan becomes a partner in his ablution, and if he eats food, drinks, wears clothes, or does any other action, it is appropriate for him to say Bismillah at the start of that action. If he does not say it, Satan is involved in that action.

3- Washing the hands from the elbow to the fingertips, or up to half the shin, or the palms before placing them into the water container, followed by washing the areas of the body that have become impure:

روایت اول: مُحَمَّدُ بْنُ عَلِیِّ بْنِ الْحُسَیْنِ فِی الْخِصَالِ بِإِسْنَادِهِ عَنْ عَلِیٍّ فِی حَدِیثِ الْأَرْبَعِمِائَةِ قَالَ إِذَا أَرَادَ أَحَدُکُمُ الْغُسْلَ فَلْیَبْدَأْ بِذِرَاعَیْهِ فَلْیَغْسِلْهُمَا

📚Khasa'il, Vol. 2, p. 630

Translation: Amir al-Mu'minin (AS) said: When one of you intends to perform Ghusl, he should first wash his two forearms (from elbow to fingertips).

Second narration: Hukm said: I asked Imam Sadiq (AS) about Ghusl from Janabah. He said: Pour water on your right hand and wash it, then wash any part of your body that has become impure, then wash your private parts...

📚Tahleeb, Vol. 1, p. 139

✅Note: According to the narration in Kafi, Vol. 3, p. 43, if the hands are not impure, the washing of the hands is not obligatory.

4- Washing the private parts, performing Mismag (gargling) and Istinshaq (inhaling water into the nose), pouring three handfuls of water on the head and washing it, and pouring water twice on the right shoulder and twice on the left shoulder in order:

First narration: Zarara said: I asked the Imam about how to perform Ghusl from Janabah. The Imam said: If your hands are not impure, dip them in water, then first clean your private parts with three handfuls of water, then pour three handfuls on your head, then pour water twice on your right shoulder and twice on your left shoulder. This suffices for Ghusl.

📚Kafi, Vol. 3, p. 43

Second narration: Abu Basir said: I asked Imam Sadiq (AS) about Ghusl from Janabah. He said: Pour water on your two hands and wash them, then dip your hands in the water container and wash your private parts, then perform Mismag and Istinshaq, then pour three times on your head and wash your face...

✅Note: According to narrations, Mismag and Istinshaq are not obligatory:

قَالَ وَ رُوِیَ فِی حَدِیثٍ آخَرَ أَنَّ الصَّادِقَ قَالَ فِی غُسْلِ الْجَنَابَةِ إِنْ شِئْتَ أَنْ تَتَمَضْمَضَ وَ تَسْتَنْشِقَ فَافْعَلْ وَ لَیْسَ بِوَاجِبٍ لِأَنَّ الْغُسْلَ عَلَی مَا ظَهَرَ لَا عَلَی مَا بَطَنَ

📚Ailal al-Sharaya, Vol. 1, p. 287

Translation: Imam Sadiq (AS) said about Ghusl from Janabah: If you want to perform Mismag and Istinshaq, you may, but it is not obligatory because Ghusl is about purifying the exterior, not the interior!

Note 1- Except for the Ghusl of the deceased, which slightly differs from Ghusl of Janabah, no specific narration has been found regarding differences between Ghusl of Janabah and other Ghusls.

Note 2- During Ghusl of Janabah and Ghusl of Friday, specific supplications are mentioned in the narrations, and their blessings should be utilized.

Note 3- After pouring three handfuls of water on the head or twice on the body, if any part remains dry, it is necessary to rub it with the hand and wash those dry parts.

Imam Sadiq (AS) said about someone who missed a part of their hand or body in Ghusl from Janabah: If they are certain and there is no moisture left in their body, they should return and wash that part. (📚Tahleeb, Vol. 1, p. 101).

Note 4- The order mentioned in the narrations should be observed, especially giving priority to washing the head over the body:

Imam Sadiq (AS) said: If someone performs Ghusl of Janabah and washes his head while sitting, then wants to wash his head again, he must repeat the entire Ghusl.

📚Kafi, Vol. 3, p. 44

Note 5- There are many other rulings and issues related to Ghusl, which will be presented upon the request of the believers.

اللَّهُمَّ فَصَلِّ عَلَی مُحَمَّدٍ وَ آلِ مُحَمَّدٍ وَ عَجِّلْ لِوَلِیِّکَ الْفَرَجَ