The 27-year-old model-and-actress attended the Netflix Primetime Emmys after-party, at which she wore a stunning sheer black dress and offered fans valuable advice on how to tell how see-through your outfit is.
The brunette beauty posted a photo of herself posing in her black ensemble on her Instagram account as a friend shone a light on her.
She wrote: "Real friends take flash pics to see how sheer your dress is before you leave the house. (sic)"
Emily was flooded with comments from her 19.5 million Instagram followers who loved her look, and appreciated her sharing her fashion hack.
One user wrote: "How you manage to make the most simple photos so lovely and personal is beyond me, but keep doing it. You're inspiring models, photographers, and generally the whole industry over. (sic)"
Another said: "Thank you! This is actually so helpful!"
Emily is no stranger to showing off her body for her work and on social media, and recently stripped down to her underwear for a new ad campaign.
The sultry brunette beauty dressed up as a sexy secretary in a pair of skimpy tights, a laced romper and a flattering bra for DKNY's new lingerie collection.
Despite posing in an array of positions - including being sprawled across the bed flashing her pert posterior - the 'Gone Girl' star claims in the campaign that she's "far from perfect".
Speaking in the campaign, she revealed: "Underneath it all, I'm far from perfect. I'm a little crazy. Just a little. I like to make my own choices but it can be hard to choose. I don't need permission to be me, I'm tender and I'm tough. Nothing is ever just black and white."
The ad campaign continues with Emily - who signed up as the brand's spokesmodel in 2017 - describing herself as a "hopeless romantic" who is "never satisfied".
Emily - who is married to actor -and-producer Sebastian Bear-McClard - added: "I believe that all women are powerful. Like, really, really powerful. I'm not afraid of change. I'm a bada**... don't you think? Underneath is all I'm just me."