If we are talking about weddings' outfits there's something you should know: It's better to be overdressed than underdressed.
If you received an invite that says "black tie optional," you should wear a long dress. Why? it's better to be safe than sorry.
One of the most important things to remember when shopping for a wedding is you want to look cool and stylish, but classy at the same time. Do not forget that you are going to a formal celebration, so you should dress properly and don't ever, ever wear white to a wedding.
If your wedding is on daytime you can wear a cocktail dress or mini dress but the length should be to the knee, never less than that. Bodycon dresses are not recommended for weddings, a bodycon dress is perfect for your next Saturday night out with the girls but not for a formal event.
Let me know your thougts!