Ballari Jn - Look around and enjoy the station. A sacred place where Mahatma Gandhi once spent 8 hours. - Vishwanath Joshi

Before you fill up form you need to know:
Train name and number,
date of travel
Class of Travel
berth/seats to be booked
From...
more...

stn/to station,
Boarding station (optional)
Passenger names/ gender / age
choice of berths in case of sr.citizen or female.
Onward journey : if you want to do...
same as above....
applicant's : Address, time and date of booking, phone no.
In case you are trying to get Tatkal: carry photo ID, if ticket if for others, carry sighned photo ID of other person. with a request to book ticket to stn. master.
In case you want to avail concession, you need to show your documents. and if PRS man wants copy, carry xerox also.
In case of doubt put your question further.