now sure how old you are but in a wedding you want to dress nice.
wear a suit with matching pants and blazer, get it together. worse thing you want to do is get something that color don't match.
aside from the fit, there's one thing i look for.
3 button
mostly wear this for a event, you won't wear these 3 button on a casual day
2 button
1 button.
2 button and 1 button can be worn casually without looking too overly dresssed.