How to pick a vest, a shirt and a tie for a wedding
Most guys can figure this one out much more easily than the tux. But here are some simple rules to avoid "I should have worn..."'s when you're looking at the wedding photos two weeks after the wedding.
Select a wedding tie
Opt for a solid color, not patterns or boxes. At most, choose simple stripes tie (preferably horizontal rather than vertical). The tie has to match the color of your boutonniere (a flower you'd put in the front chest pocket of the tuxedo) if you have one.
Oh, and *are you absolutely sure* you know how to tie a tie? Practice, practice, practice! It's a very common last-minute issue when a groom is looking for help in tying a tie for him on the morning of the wedding. Can be pretty embarrassing!
Select a wedding shirt
Of course, some brides demand a "theme" - meaning your boutonniere, or even the entire shirt, might need to be in a certain color. Unless she requires a certain color, go for a crisp, blue-ish bright white shirt. Generally, the only other shirt color other than bright white that you might decide to go with is purple shirt. After all, purple is considered to be one of the most popular wedding colors. No other color should cross your mind!
Where should you get the shirt? WeddingVenture.com recommends against buying the shirt at the same place you buy the tuxedo. When you buy a tuxedo, you want to reduce the number of variables and only focus on the tux. Come to the tux shop with your own new shirt - most tux shops are used to that.
Among popular retailers, stores like Macy's, surprisingly, have decent selections of shirts. For the weddings, always choose solid white, fitted, wrinkle-free option. Since shirts are often packaged, tux shops can be unnecessarily reluctant to unpack sealed shirt packages "for you to try a few." Instead, tux shops often have opened shirts that everyone uses to try how the suit would look with a white shirt, but that "trial" shirt is usually a few sizes off (it's meant to be one-shirt-fits-all [customers]) and does not let you fine-tune your wedding tuxedo well.
Select a wedding vest
Whether to buy a vest is a matter of preference. As a thought, consider having a vest if your wedding takes place October-June; having a vest in the heat of the summer may not be a good option as it will be too warm.
Color-wise, vests generally follow the same guidelines as the shirts. In addition to white and purple, however, vests have two other options for colors: dark purple (to contrast a purple shirt) and aquamarine (another popular "wedding color"). Leave the gray and black-and-white vests for your groomsmen.