At some time or another, all of us will have smeared a bit of sample concealer or eyeshadow on the back of our hands to test out the colour - although few people would actually think of applying samples to their faces every day as part of their make-up routine.
For 18-year-old Amira Saskia however, beauty shops can double as “mobile make-up collections”, with the London-based social media manager regularly applying public testers to her face while getting ready.
In a number of TikTok videos that have since gone viral, Amira can be seen painting her face using beauty products dotted around on counters throughout the city.
Her hack has received a somewhat mixed response, with some followers blasting her as "unhygienic".
However, Amira isn't too fussed about the criticism, reasoning, "as long as I have a good primer, I don’t care".
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One clip, which has clocked up more than 7.3 million views and 931,000 likes, sees Amira applying a NARS branded concealer, adding lipstick and contour to complete her look, all while remaining undetected.
A separate video, which has had more than 1.1 million views and 112,000 likes, sees Amira begin by using basic skincare before grabbing free make-up samples dotted around Harrods' beauty counters.
In the vid, Amira applies luxury a La-Mer moisturiser, before proceeding to test match her perfect foundation shade from upmarket make-up brand NARS, all while using publicly available temporary application brushes and wands.
At one point, a member of staff asks if Amira needs any help, but doesn't appear to call her out on her behaviour.
One concerned user wrote that they were "praying for your skin", while another remarked that her actions were "unsanitary".
A third winced, “It’s giving pink eye and cold sores lol,” as a fourth shuddered “They did this study and found fecal matter in testers lol.” [sic]
However, not everyone was opposed to Amira's thrifty makeover hack.
A different user commented, "These [videos] make me happy".
Someone else agreed: “I’m convinced if you do anything with confidence, people don’t question you".
Amira has since gone on to defend herself against negative comments, explaining that she “likes to experiment” when it comes to make-up and that she has rarely experienced any skin complications.
She said: “Some say they love my confidence and others say it’s unhygienic – but as long as I have a good primer, I don’t care. Most of the time staff admire my confidence and I make connections with them by asking for advice on my make-up.
“Five times out of ten, I end up buying something. It’s pointless [though] as there are hundreds of make-up shops I can use every day. I’ve been doing this my whole life as I don’t see it as a shop.
"I can use [them] at any time, to do any look I want, to get ready in minimal time. I have never let hate bother me, because if they don’t know me personally - why would I take it personally?"
There have even been some positives to come out of Amira's cosmetics controversy, with her very own beauty brand - a hair oil called Drop of Gold - seeing record sales thanks to her getting plenty of online attention.
She continued: “Any publicity is good publicity and just from that video, I sold 941 bottles of my hair oil in just a day, which is insane.
“Yes, some people scroll past the video and think I’m embarrassing myself, but I see a genius strategy of selling my oil and growing my following".
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