- Wear a suit. Business professional means that you should wear a suit. This can either be a skirt set or pant set.
- Suit colors - black, grey, or khaki. Color options are limited with the color of the suit but the blouse or shell underneath can be nearly any color. There is also the option of a navy suit but it looks a bit outdated to me.
- Conservative vs. modern. For a more conservative look then stick with the common styles but if you want something a bit more modern there are wide variety of options. Just be cautious with more modern looks, so as to not lose the professionalism.
- Blazer or sweater. Always wear either a sweater or a blazer. There is always the option to remove this layer at work, if your blouse underneath is work appropriate. A blazer always makes an outfit more professional. Even on hot days another layer may be necessary due to excessive air conditioning.
- Keep shoulders covered. I'm a believer in keeping your shoulders covered. This removes any issue of your bra straps showing. There is also the concern of showing your bra in the underarm area. More casual offices may be more lax on this. If you choose to wear anything that is sleeveless, then it is necessary that you have a sweater or blazer available.
- Clothing options - trousers, skirts, or dresses. Business casual allows for a greater variety of clothing options. If you want a more clean look, then choose clothes with clean lines that are well tailored. In other words, flowy summer dresses are less professional.
- No miniskirts. Skirts and dresses should reach the knee or meet right above the knee. You shouldn't be worried about your underwear showing at work.
- No cleavage. There is a time and a place for a bit more risque clothing but that is not at work. There are a variety of camisoles available that can be layered underneath most clothes. It's also a good idea to wear camisoles under a blouse. I recently went to a job interview and realized, afterward, that my blouse was see-through in certain lighting. Oops.