Shoes tell your age

For those who want to enjoy the charm of puzzle,  may not read further. But for those who may wish to churn the brain here is hint. Shoe size doesn't matter take any digit from 1 to 9. Step 2 and 4 makes it 100 times. eg. 5 to 500 and so on.  Now, steps 3 4 and 5 equals to 2012. When substracted by step 6 gives your age in double digit. Final answer always in 3 digits!!!!