Give your closet a thorough look and search for items that are classy yet simple. Casual dress works best for auditions unless it was previously told that you need to be formal. The dress doesn't need to be unflattering: it should be trendy but not very bold. You could wear dark jeans with a casual shirt. The outfit should allow you to get completely lost in the character but should also show that you have a personality of your own. There are small details which you need to consider, it could be defined cuts, different stitching, buttons which are antique. It will help you get noticed in a crowd but will not distract from your performance.
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If you think that a certain item will improve your performance then add it to your basic outfit. Add a single prop which relates to the character. For example if you are playing a surgeon, there is no need to go to the audition wearing a complete overall, lab coat, safety goggles and gloves, you will be considered amateur. You could choose a small accessory such as stethoscope or a surgical mask; it will give your act a boost. The part for which you are practicing should have an impact on your dress in small ways which will be apparent and also persuasive. If you are playing the part of a fashion model, then you need to dress up in a way that your curves are prominent and your figure is highlighted. Also, apply some makeup and give some time to your hair. Keep the colours and fabrics simple. Do not wear clothes that are very exposing as it gives a bad impression.
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Have a dress rehearsal at home. Practice your lines, wearing the same outfit that you will on the final day. This way you can observe yourself in the mirror and also take opinions from others regarding the appropriateness of your dress. You need to be satisfied with your dress on the final day.
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