The chart-topper uploaded a short video to her official Snapchat account on Saturday.
In the clip Sarah, 38, can be seen smiling as she gets her hair done.
Rocking large shades, Sarah smiles as she filmed herself for her fans.
With her hair in foils, Cheryl's former bandmate appeared to be dying her hair a new shade.
Sarah added the song Sunday Morning by the Velvet Underground over the clip.
Last month Sarah heartbreakingly told fans she is battling cancer.
The brave starlet wrote: "Earlier this year I was diagnosed with breast cancer and a couple of weeks ago I received the devastating news that the cancer has advanced to other parts of my body.
"I'm currently undergoing weekly chemotherapy sessions and I am fighting as hard as I possibly can."
Sarah added: "My amazing mum, family and close friends are helping me through this, and I want to say a thank you to the wonderful NHS doctors and nurses who have been and continue to be heroes.
"I am doing my very best to keep positive and will keep you updated here with how I’m getting on.
"In the meantime I hope you’ll all understand and respect my request for privacy during this difficult time. Sending you all so much love….xx"
After hearing the news, Sarah's ex Chad Johnson, who found fame on the US show The Bachelor, revealed he is praying for her.
"Sarah always reminded me of my mum and my mum went through the exact same thing," he told the MailOnline.
"It sucks, I am hoping and praying the absolute best for her because I know how difficult the situation can be.
"My mum had breast cancer and it got into her blood and her liver. I know what Sarah is going through, I mean, I have seen it from day one to the very end and I just hope that she can recover."