Rihanna sets her eyebrows with a bar of soap.
The 'Work' hitmaker's make-up artist, Priscilla Ono, recommends putting a brow brush into a solid cake of soap and sweeping it over the hairs after they've been filled in with colour in order to stick them in place while maintaining a realness in order to get a brushed up and thick style.
She said: ''It's an old make-up artist trick and because everyone's obsessed with an editorial brow, this really makes them stick.''
Rihanna's own Fenty Beauty collection boasts 40 shades of foundation and the 30-year-old singer doesn't just stick with one of them as her skin tone changes on a daily basis.
Priscilla told Harper's Bazaar: ''If your face is lighter than your body, match [foundation] to your body rather than your face.
''[Look in the mirror and] put your shoulder to your cheek to see if it matches.
''We do this all the time because [Rihanna's] skin tone changes all the time. She gets tan really easily but she also lightens up really easily.''
Meanwhile, Priscilla recently praised her famous client as a ''dream'' to work with.
She said: : ''It's a make-up artist's dream... it's just a really amazing experience. It's like hanging out with your girlfriends, painting your toes, rollers in your hair! It's like that vibe.
''When you're with her all of that [fame] goes away and she's just like your girlfriend, it's one of the best feelings, really.''
Priscilla admitted that the 'Diamonds' hitmaker is extremely accomplished in beauty, and she's even picked up tips from her famous client.
She said: ''She's amazing at doing her own make-up; we call her a make-up artist in her own right.
''I think that from working in this industry for so long she's really perfected her face and she knows her face better than anyone.
''So for me as a make-up artist ,at the beginning it was intimidating, like 'Wow she can do her own make-up so well', but she's actually taught me a few things along the way as well.''