Related income tax return

Dear sir,

my salary is Rs, 1,80,000 annual which does not come under tax liability, i know that it is not compulsory to submit the return whose salary is not taxable. but i want to submit my return for assessment year 11-12. can i do the same or not and what is date after going on 31 Jul for submit of ITR for 11-12.

Its very urgent. also send the process of Efiling process of filing of ITR.

regards,

pardeep kaushik