The rule of thumb is 'don't wear white' as that, or some variation of it anyway, is generally the colour most brides opt for.
Apart from this widely-held belief, we would have thought you can wear pretty much what you want but Lauren Conrad thinks differently on the subject.
In a recent interview with Who What Wear, she was asked what her opinion on how wedding guests should celebrity dresses uk.
Lauren, who first came to our attention on MTV show The Hills, started off by explaining that "there's a lot to consider" when it come to wedding guest outfits.
Appropriateness is "really important" and she recommends the option of layering if the wedding is held in a church.
Then, and this is where people might have an issue, she says steering away from anything "loud" is the best idea.
"Wearing anything loud, that could be anything from color to hemline, is usually not appropriate. I think anything that distracts from the bride is good to avoid".
Every bride is different but we bet most probably want their guests to have a good time and not spend too much time stressing about what to wear...
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