Need advice from fellow SAPian

My brother works as a SAP MM enduser type role in Mylan product company.

He does works with the Purchasing teams and signs of all the deals with the agents. PO creation , STO things . Typically i say enduser roles if he faces any issue in it he raises to MM IT people to resolve it.

Since the payball is quite low here around 12LPA But perks were good.as he doesn’t want to switch to IT company and pressure to handle off is quite tough transition i believe.

Any suggestion on how to excel in prior as the promotion in progress and how to pace up the salary wise?