Hadith: When the Messenger of Allah (may Allah's peace and blessings be upon him) entered the privy, a servant and I used to carry a waterskin and a pointed staff, and he would cleanse himself with water.

عَنْ أَنَسِ بْنِ مَالِكٍ رَضيَ اللهُ عنه قَالَ:
كَانَ رَسُولُ اللهِ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ يَدْخُلُ الْخَلَاءَ، فَأَحْمِلُ أَنَا وَغُلَامٌ نَحْوِي إِدَاوَةً مِنْ مَاءٍ وَعَنَزَةً فَيَسْتَنْجِي بِالْمَاءِ.
[صحيح] - [متفق عليه] - [صحيح مسلم: 271]

Anas ibn Mālik (may Allah be pleased with him) reported:
When the Messenger of Allah (may Allah's peace and blessings be upon him) entered the privy, a servant and I used to carry a waterskin and a pointed staff, and he would cleanse himself with water.
[Authentic hadith] - [Narrated by Bukhari & Muslim] - [Sahih Muslim - 271]

Explanation

Anas ibn Mālik (may Allah be pleased with him) reports that he and a servant of similar age would follow the Prophet (may Allah's peace and blessings be upon him) when he went to relieve himself. They would carry a stick with a pointed end like a spearhead, which he would insert in the ground to hang a covering as a screen for his privacy or as a Sutrah (barrier) for his prayer, and would carry as well a small leather vessel filled with water. When the Prophet (may Allah's peace and blessings be upon him) finished relieving himself, one of them would hand him the water vessel, and he would cleanse himself with it.

Benefits from the Hadith

1. A Muslim arranges his cleaning supplies beforehand when relieving himself, to avoid having to move and get dirty afterward.
2. Concealing one's ‘Awrah (private parts) while relieving oneself, so that no one may see it, because looking at ‘Awrah is forbidden. Thus, he (the Prophet) would fix the stick in the ground and drape a covering garment over it as a screen.
3. Teaching Islamic manners to children and raising them upon these values, so they may inherit them.