WHICH BUTTONS DO YOU BUTTON UP WHEN WEARING A SUIT JACKET?
A suit jacket should always remain buttoned until you sit. Once you stand up again, the jacket should be refastened. You also have to consider that there are different rules depending on what type of suit you are wearing and whether you are standing or sitting down when wearing the jacket. In short: Single-Breasted Suits 1. For one-button suits, that one button should always be buttoned up. 2. On two-button suits, the top button should remain buttoned, while the bottom one is left undone. 3. With a three-button suit, you can either button the top two and leave the bottom unfastened, or simply button the center one.
For the double-breasted suits, you should only fasten the top button and leave the bottom one open.
dolce & gabbana