Shopping for a wedding dress is exciting (congrats if it's on your to-do list!). It's tempting to book the first appointment possible and run straight in, but let's talk—this is one of those situations where some thoughtful prep is a good idea. Before you head in, make sure to plan out what undergarments you wear or bring.

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The bra

Wear or pack a strapless style. Even if you think you want straps on your gown, you'll likely still end up trying on a few sans coverage and you'll want to see what it looks like without unsightly bra straps. Underpinnings can make a huge difference in how a garment fits and looks, so do your best to figure out what bra you'll likely be wearing on the big day (it's fine to shop after you've found the dress, but avoid bringing in an old number you kind of hate and barely fits). If you're like me and do not want to wear a bra, don't. I knew whatever alterations I had done to my dress would include fixes to make sure it'd work without one, so I tried everything on freestyle: I wanted to see what my upper half would look like without added padding or oomph.

The underwear

This isn't the time to be distracted by panty ines or the peek of hot pink lace. Wear the plainest, simplest pair of undies you've got in your drawer.

The shapewear

I called in the experts for this one: the pros at Spanx, who I bet outfit at least half the world's brides. They recommended the brand's In-Power Line Super High Footless Shaper for coverage from below the chest to the midcalf and said it's one of their most versatile for when you're not quite sure what you'll be trying on. It sits under the bra too, smart so you can wear whatever piece you prefer, and at $28, it's not too painful on the pocketbook.

In terms of non-undies, don't forget a ponytail holder and a pair of shoes that are a similar height to what you plan on wearing on the big day. The hair elastic is vital so you can see what the neckline and back of the dress look like (and, honestly, you might work up a little sweat trying on all those beautiful dresses). A lot of stores and boutiques have shoes for the exact purpose of trying on dresses, but I'd rather bring a favorite pair than slip into something that doesn't fit or isn't your style.

Also, bonus points if you think ahead and bring a mini bottle of champagne. I mean, what could be better than toasting the perfect dress?

See also: formal dresses online