I WANT TO DO IIT AFTER 12,WHAT STEPS SHOULD I FOLLOW?

@ xavier 
For doing iit after 12 , u need to first clear jee main , thats the first level entrance exams , and after that u need to clear jee advanced with a rank within 9500 to get into an iit , 
even , for that u need to do some hard work as iit demands it . 
1- frst of all your concept needs to be crystal clear and for that u need to read ncert throughly . 
2- after that follow some standard books for JEE , but remember to stick to any one books . 
u can try the following 
1- PHYSICS BY H C VERMA 
2- ORGANIC CHEMI BY O.P TANDON 
3- PHYSICAL CHEMI BY P BAHADUR 
3- INORGANIC CHEMI BY J D LEE . 
4- MATHS BY M L KHANNA . 
after that precice some of the previous year jee question as soon as you complete 1 chapter . 
AND MAINLY focus on problem solving rather than reading the theory , beacuse , jee demands problem solving . 
and most important one , never loose your sleep and personal hobbies , they should have to be maintained with preparation . 
ALL THE BEST ..