Income tax practitioner

Dear all, Please guide me for getting Income Tax Practitioner number from Income Tax Dept. 1. What is the benefit of If I get Income Tax Practitioner number from Income tax dept. 2. How to get Tax Practitioner number from Income Tax Dept. 3. Mandatory to sec 288(1) as per income tax act as mentioned in the form No. 39 as "Designation of the income-tax authority before whom appeared" 4. Other info about Tax practitioner please provided Thanks