1. The Prophet (pbuh) said :When one of you sneezes he should say,
Alhamdhulillah
اَلْحَمْدُ للهِ
Meaning:
Praise be to Allah
2. Upon hearing this,his brother or companion should say to him,
Yarhamukallah
يَرْحَمُكَ اللهُ
Meaning:
May Allah bestow his Mercy on you
3. Upon hearing this, one who sneezed shall say to him,
Yahdheekumullahu wa yuslihu baalakum
يَهْدِيْكُمُ اللهُ وَيُصْلِحُ بَالَكُمْ
Meaning:
May Allah give you guidance and improve your condition
(Book: Bukhari 6224)