Summarize:

Familiarize yourself with your company's dress code and dress for your banking job based on those guidelines. The dress code will give you a good understanding of how you're expected to look and ensure that your wardrobe meets banking and company standards. The dress code will make you aware of the minimum requirements of the job. You should also observe your peers and verify that you are dressing in a way consistent with the local norms. Ask about casual days within the company or bank branch. On casual days it's often appropriate to wear clothes that would otherwise be considered too casual for the banking industry. Casual Fridays are not as common as they once were, but they do exist even in high-level investment banks. Barclays has instituted a policy whereby jeans and t-shirts are acceptable on Fridays. Jeans and t-shirts, however, are generally considered too casual even for a casual Friday. Dress for bank employment by starting with comfortable shoes. You'll be on your feet a lot, so choose shoes that can have inserts placed in them to absorb shock and cushion your feet. Stick to closed-toed, low-heel dress shoes. You should dress for a bank job neatly, cleanly and conservatively. Iron out any wrinkles, tuck in your shirt and don't wear anything stained or ripped. A client or customer that sees these details will change their opinion about you and your bank for the worse. Mend or replace these items so they don't make you look sloppy or unprofessional. To look professional at your bank job, eliminate any body modifications like piercings or tattoos from your client's line of sight. Keep ear piercings tasteful or small, remove facial and tongue piercings and cover tattoos with pants or long sleeves while you're at work. Check shirts and sweaters to ensure that they cover your stomach and midriff without exposing too much cleavage. Be sure that your skirts are an appropriate length for the workplace by not wearing any that don't at least reach your fingertips when your hands are down at your sides. Anything shorter, or with a slit that goes higher, isn't appropriate for work attire. Most of the details of your attire should vary little from what you wore during your interview. If you are employed as a teller though, you might not be expected to wear a suit jacket once you start on the job. Observe what others in your position wear. For any higher ranking position, assume that you should wear a suit jacket and that your attire should vary little from what you wore during your interview.
Read the dress code. Ask about casual days. Choose comfortable and professional shoes. Keep everything neat. Cover piercings and tattoos. Wear clothes that are an appropriate length. Know when to wear a suit jacket.