In an interview for Yahoo! Beauty, Aniston revealed the secret to her casual, yet chic look is customization.
"This is my secret: The trick to T-shirts is I that I usually tailor them. Which is silly, but it works. Or you just have to find the perfect one," she told the makeup icon.
For jeans, Aniston, 45, says she also makes subtle yet, effective changes.
"I take the pockets off of Hudson jeans, because I like the fit, but not the pockets ... And I wear Saint Laurent jackets," she said.
There you have it - don't be afraid to alter your jeans and t-shirt, Jen does and the former "Friends" star never looked better.