Choose a medium weight or heavy fabric with 20 - 40% stretch. For example terry, sweatshirt jersey or a heavier teddy or cable knit. Be careful with fabrics that are very drapey and soft, as they might make the pockets look untidy. In such case, consider omitting the front pockets.
For the pocket bags, pick a medium weight, sturdy knit fabric that matches your main fabric. Ponte is a great choice, but make sure your pocket bag fabric isn’t heavier than the main fabric. You can also use your main fabric for the pocket bags.
This pattern comes with plenty of ease. Check the finished measurements for your size and, if necessary, select a size smaller than usually if you want the garment to be more fitted.