As I understand it, you can only write off your clothes if
1. They're required for your work
2. They're too outrageous to be civilian clothes
3. You've never worn them in your personal life
There have been a number of famous court cases for this. One with a lady who worked for a fancy boutique, and had to buy stuff in order to work as a sales associate (ie had to buy suits in order to sell suits). She somehow proved that she never wore the clothes in her personal life,...