As you want to get the some important tips for IIT JEE preparation from 11th class without any coaching so here is the information of the same for you:

Firstly you must be clear and sound with your basics

You need to practice more as you not thinking because IIT entrance is so tough than expectation

For this you need to clear your basics first because in IIT entrance 70% syllabus come form 11th class

And from 10+2 only 30come so practice about 11 and 10 class syllabus and take help from your class teachers and your classmates