What must one who paid for an alcoholic drink for another person do to atone for this sin?

A Hadith (definition) was authentically narrated from Anas and Jabir that the Prophet, peace and blessings be upon him, said: "Every son of Adam commits sins, and the best of those who commit sins are those who repent." Repentance is accepted from whoever repents promptly and performs righteous deeds. The conditions for repentance are: abandoning the sin, regretting it, and resolving not to return to it. The brother must be advised to avoid bad company.