Combining a blue double breasted blazer with a long sleeve shirt is a nice choice for a classic and elegant getup. You could perhaps get a bit experimental in the shoe department and complement this look with a pair of navy and white low top sneakers. One actually can look light and breezy under the summer heat. The proof is right here As a 30-something Millennial gent, you want to start dressing more professionally. That's when looks like this are a surefire option.