Check the seams, neckband, and hem.
They should all lie flat and look smooth.
Pay attention to the shoulder seams.
Make sure that they are symmetrical.
Skip tees with tight or wrinkled underarm seams.
They’re signs of poor construction.
Check the weight of the fabric.
Unless the T-shirt is of the “tissue tee” sort that’s meant to layer, you’ll want to be sure that the fabric is heavy enough to conceal your bra. Pull the shirt over your hand to check for transparency.
Look for the most flattering neckline.
V-necks flatter large chests, scoop necks elongate the neck, and crew necks enhance small busts.