Reach for a mustard long sleeve shirt and white shorts if you seek to look casually cool without spending too much time. A pair of loafers will give a different twist to an otherwise standard ensemble. This getup is a never-failing option if you're looking for a great, summer-appropriate getup. As you're moving from your 20s to your 30s, you probably want to start dressing more like a mature gentleman. In this case, getups like this are a tested option.