Very easily you can book train tickets. The options are ...
i) Go to the nearest PRS Reservation booking centre. Note : Booking possible from Any PRS office in India .....for a ticket from any place to any place.
ii) Go to IRCTC website, register yourself and follow the booking instructions.
Use your bank account / credit for payment purpsose....
more... You can view which banks and credit cards are approved for payment purposes by IRCTC.
iii) Take the help of ICRCT authorised agents for booking rail tickets. Here on the top this page... or the right hand side, there is a list of authorised IRCTC agents. Just click on and contact any of them. The IRCTC autho agents' service charges are prescribed by IRCTC.