Seren Jenkins, 19, from Blackwood in Caerphilly, is in remission after treatment for Hodgkin Lymphoma and wants to raise awareness of the issue.
The Teenage Cancer Trust says appearance is one of the biggest worries patients face, behind survival.
It is an issue Seren knows about too well after losing her hair.
She was diagnosed with Hodgkin Lymphoma, an uncommon cancer that develops in the lymphatic system, which is a network of vessels and glands spread throughout your body, in February and had to undergo chemotherapy.
“When I was diagnosed with cancer I cried as I was upset that I was going to lose my hair,” she said.
“I used to dye it all different colours and loved having colourful hair, I see it as a form of self-expression. To think then that I was not going to have any hair to essentially destroy and go crazy with was quite hard.
“I almost felt like I didn’t know who I was anymore. My hair was such a big part of me.”
Seren began experimenting with different coloured wigs, buying eight in different colours, but eventually got the courage to start going without them.
She is one of 20 young people across the UK taking part in the #StillMe campaign from the Teenage Cancer Trust.
In a survey of 53 patients, the charity found 23% of those surveyed were most worried about the change in their looks, which can include hair loss, scarring, weight fluctuations, facial tumours and amputations.
Some 21% were most worried about painful or lengthy treatment, while 39% were most concerned about survival rates.
Seren now wants to help those who are worried or losing confidence feel more comfortable about the changes their bodies will go through.
“It’s liberating in the way to look at and be the end product.
“There was a girl that started [treatment] when I was finishing and she was on the same treatment as me and I was able to explain the changes that were coming and the changes that were coming and it made her feel better, but I didn’t have that.
“I want to raise awareness. I didn’t think that I was young and this was an old person’s disease, but to go to the Teenage Cancer Trust and be able to see the amount of young people that are dealing with it is just shocking.”
Kate Collins, chief executive of the Teenage Cancer Trust, said: ”The ‘ideal’ bodies and looks portrayed on Instagram that many young people aspire to are difficult to live up to at the best of times – and the effects of cancer and treatment on appearance, like losing hair can really add to this pressure.
“People like Seren are sharing their experiences of how they coped, and this will do so much to help other people facing similar issues. We’re really proud and grateful that she is part of our still me campaign.”