U'll have to take up the Civil services exam (The same as for IAS, IPS etc).. Once u clear the priliminary, u'll have to prepare for the mains.. While choosing the options (such as IAS, IPS, IFS etc), u'll have to choose IRS (Indian revenue Services).. If u clear the exam & the interview, u'll become the Commissioner of Income Tax..
For further info go to http://www.upsc.gov.in/general/civil.htm