Allah’s Messenger is reported by Imam al-Baqir (a.s) as saying:
خَمْسٌ لَسْتُ بِتَارِكِهِنَّ حَتَّى الْمَمَاتِ: لِبَاسِي الصُّوفَ، وَرُكُوبِي الْحِمَارَ مُؤكِفاً، وَأكْلِي مَعَ الْعَبِيدِ، وَخَصْفِي النَّعْلَ بِالْيَدِ، وَتَسْلِيمِي عَلَى الصِّبْيَانِ لِتَكُونَ سُنَّةً مِنْ بَعْدِي.
I will not quit five habits until the moment of my death: wearing coarse clothes, riding a mule without packsaddle, eating with the slaves, weaving footwear with my own hands, and saluting children so that it will become a tradition after me.
source : http://www.maaref-foundation.com