The dress should be covering your body properly, not tight and not see through and not revealing your awrah or part of it. There is no problem if you wear it for the wedding only or carry the bouquet.

 What are the characteristics of the wedding dress that would render it to be halal, other than covering the awrah perfectly, and it’s reasonable in price, plus it’s wearable even for other occasions not just the wedding day. Is wearing a special dress on my wedding day considered to be imitating the kufars? What about holding a hand bouquet?