LONDON-Cara Delevingne wants to help young people to learn to open up more.

The 'Valerian and the City of a Thousand planets' actress admits she struggled as a teenager because she was unable to ask for help or express how she truly felt, and she wants other young people to learn to open up more so they never have to feel the pain she did.

She told ELLE magazine: ''Probably a teenager [was the hardest time], especially with school and not giving yourself a break. And not asking for help, or saying, I'm really struggling.' That was the biggest lesson I had to learn, to communicate my emotions properly.

 I'm still learning how to do that.

''It felt like I was completely alone and I couldn't express myself because I felt ashamed of my emotions. I want to make sure kids see that emotions and vulnerability are important and should be spoken about. We're alone, but we're all in this together. We're all humans, going through the same things.''

The 25-year-old beauty will release her debut novel for young adults, 'Mirror, Mirror', in October and was inspired to write the book because she's always had a ''wonderful connection'' with teenagers and hopes the novel can help them with the issues they face.

She said: ''I've always had this wonderful connection with teenagers, from when I started with social media.

''Just having girls message me being like, 'I'm really dealing with the pressure of my thoughts, my friends, eating disorders.'

''That kind of thing, where I was like, I have an opportunity to really be there for them and help.

''You know, be a voice for teens and be honest as to how I suffered as a teenager.''

And after seeing how teenagers respond to her, Cara thinks it is very important to be a positive role model.

She said: ''When you're a teenager, you're looking for someone to idolise. Seeing the effect people like me have on teenagers now has really made me conscious of kids having strong, positive role models who are trying to do good outside of themselves.''