Messenger of Allah (PBUH) liked to use his right hand in all matters: in combing his hair and wearing his shoes.
[Al-Bukhari and Muslim]
`Aishah (May Allah be pleased with her) reported:
Messenger of Allah was used to using his right hand for performing Wudu' and for eating his food whereas he was used to using his left hand in his toilet and for other similar purposes.
[Abu Dawud]
Commentary:
Messenger of Allah (PBUH) used to use his left hand in washing his private parts and cleaning his nose and similar things, Muslims are obliged to follow his example.