The 25-year-old model-actress said she decided to go for modelling as she thought being a model may help her ultimate designing goal, reported Contactmusic.
"I always wanted to go to fashion college. I got diverted. I got swept away to model and I thought, 'Well it will at least give me some experience within the industry and I'll hopefully get to work different designers from all over the world' - which is what I managed to do," she said.
Rosie recently created her debut underwear collection for British high street chain Marks & Spencer and says she felt it was the right step to take.
"From very early on in my modelling career it became apparent to me that it wasn't going to be forever, you have a shelf life. I wanted to make sure I had some form of security that didn't just depend on my appearance. I wanted to use my brain, explore it in different ways and try new things," she added.