Loose ... yet stylish!
I found that there is SO many stylish options out there... but they can be expensive. So if you opt for new trendy styles and money is not an option then a trip to your local maternity store would be your best best ... they have so much fun and festive wear that it is crazy!
However, if cost matters i found that loose works best ... wearing a larger shirt or a tank under a larger shirt works too. I always had a nursing cover up so I could wear whatever I had and nurse discretely!