Pairing a dress shirt with sweatpants is a good idea for a casually cool outfit. As a 30-year-old gent, you probably want to start dressing more like a mature gentleman. In this case, combos like this are perfect as inspiration.
Dress Shirt with Sweatpants Cold Weather Outfits For Men In Their 30s
Try pairing a dress shirt with sweatpants if you seek to look neat and relaxed without too much work. As a man in his thirties, you probably want to start dressing more maturely. In this case, inspiration like this is very useful.