Make a jaw-dropping statement anywhere you go by opting for a cardigan and a light blue dress shirt. To give your overall outfit a more relaxed feel, why not complement this ensemble with a pair of navy leather boat shoes? This getup isn't a hard one to nail and it's summer-appropriate, which is more important when it's boiling hot outside. This combination illustrates that as a 30-something Millennial man, you have a wide range of outfit options.