I'm not sure if you've thought of this, but if you plan to change from heels to flats, will you be able t odane without tripping all over the hem of your dress?
I know I won't be able to wear heels all day, especially as we're hoping to use the gardens and lawns of our venue, and I wouldn't be able to dance in heels, either, so I've opted to wear flats all day as no one will see them except perhaps the toes peeking out from under the dress, and my fiance isn't all that much taller than me.
Other people have offered good advice on where to shop. I'm probably just going to wear some toms, which are sold at schuh, office, etc:


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