Personally, I suggest that you wear whatever you feel most fabulous and beautiful in, because that added confidence boost will show in your images. I love when my clients add small details like, bright or unique jewelry to match their branding colors.
A fun print on a dress or top etc. Choose something that is comfortable and suits your style, wear what you love and feel great in. I say it is usually best to bring at least 3-4 tops with a blazer or cardigan that way we have some variety to pick from.
This is a great time to go through your closet and check out what pieces you have that match the image you would like to present when meeting with a client or customer. You can splurge on a few fun accessories to freshen up an outfit. Or, if you want to add in a few pieces missing from your wardrobe but don't want to spend a ton, check out Rent The Runway.
Don't forget to bring undergarments that match your outfits. It's always great to bring a nude bra, underwear/Spankx as well as black bra, underwear/Spankx.