From IDI Student to TV Star

Welcome to an inspiring transformation story that traverses from the precision of aerospace engineering to the creative flair of interior design. Meet Justine Guillermou, a former aerospace engineer and a proud graduate of The Interior Design Institute, who turned her lifelong passion for design into a thriving career. After spotting an opportunity on 'The Big Interiors Battle', a Channel 4 show where eight aspiring designers compete to win and design a mortgage-free apartment, Justine's career took a spectacular turn. The show, which challenges contestants to overhaul various spaces creatively and effectively, became a pivotal moment in Justine’s design journey. Learn more about the show here.

In this exclusive interview, we delve into how Justine leveraged her IDI education to carve out a niche in the design world with her business, Rainbow Shaker, known for its vibrant and innovative interior solutions. Her story is not just about changing careers but about embracing the possibilities that come with pursuing one’s true passion through education and courage.

from aerospace engineer to interior designer with justine guillermou

Image source: #IDIstudent Justine Guillermou from @rainbow.shaker

"The training was amazing! The course quality and my tutor's advice were top-notch! I learnt so much and I am now confident enough to start my own business in interior design. I was also selected as a contestant on the television show, ‘The Big Interiors Battle’, where I competed against other aspiring designers and applied the skills I learnt from the course! You can watch a video interview I did with IDI here."

Meet Interior Design Course Graduate, Justine Guillermou

Hi, I’m Justine! I’m the founder and creative mind behind Rainbow Shaker and IDI graduate. I am based in London and work everywhere in Europe. You can currently see me on The Big Interiors Battle, the brand-new interior design show on Channel 4.  

What inspired you to become an Interior Designer?

When I was a child, I grew up with ongoing renovations as my parents restored a historical house from scratch. I learnt how to install wallpaper from a very young age! At that time I wanted to work either in fashion or interior design. I ended up studying and working as an aerospace engineer, but I always had to look outside of work to feed my creativity.  Fast forward a few years, I decided to follow my childhood dream and studied with The Interior Design Institute to start my own interior design business. 

interior by justine guillermou from big interiors battle tv show

Image source: #IDIstudent Justine Guillermou from @rainbow.shaker

How would you describe your design style?

I would describe my style as very colourful, playful and 100% anti-gloom (almost psychedelic)! I love to create visual illusions with paint to play with the sensation of space and volume. My colourful creations are also balanced with the use of raw materials like wood and metal. 

How were you selected for the show?

I actually first heard about the show through the IDI Facebook group. After sending my initial application with a portfolio, I did several rounds of interviews and had to submit a project mockup for a fictional space so they could get a sense of my style, how I work… After several weeks of waiting, they told me I was one of the eight contestants selected for the show. 

Did the show change your design style or approach in any way?

I love DIY-ing, but the show encouraged me to take more risks in my creations and I am using those in my designs. I was also feeling a bit of ‘imposter syndrome’ before the show but it has made me more confident in myself! 

How was being on the show compared to working on a typical project?

On one hand, it was very similar. I initially received floor plans and pictures ahead of filming. I had to design each room with a specific brief and budget. I developed concepts, created moodboards 3D models…which was the perfect opportunity for me to apply the skills I learnt at IDI. On the other hand, the whole goal of the show was to design an apartment for my own taste. So I didn’t hold back ;)!  

justine guillermou from big interiors battle tv show

Image source: #IDIstudent Justine Guillermou from @rainbow.shaker

What useful skills from IDI did you put to use on the show?

All the modules I took with IDI were extremely useful for the show. On top of what I already mentioned, what set me apart from the other candidates during the selection was my project management (Modules 7, 10, 11) and clear and concise electrical plans (Module 5: Lighting). 

What projects are you working on now?

I recently finished renovating a 250m2 workspace in Paris, applying my colourful signature. However, I made it my point to furnish it entirely with upcycle and second-hand furniture, and you can see more about it here. I am also currently renovating a boutique hotel in the heart of Paris, so it can be ready for the Olympics and Paris Design Week. I chose a very eclectic vibe with lots of colours, neon and flowers. You can see the BTS here and feel free to stop by when you visit Paris!

Give us a typical rundown of a day in your life as an Interior Designer:

After drinking my biggest cup of tea, I often start my morning by planning content for social media and checking up with clients, trades and suppliers. During lunch break I usually like to go on a walk to find new shops for furniture and accessories. In the afternoon, I work on the concept and designs of my ongoing projects. I also update the real-time tracker for each of my projects to make sure everything runs smoothly. In the evening, I sometimes go to networking events. 

justine guillermou interior design

Image source: #IDIstudent Justine Guillermou from @rainbow.shaker

What advice would you give to new students?

Always remember that if your clients hired you it’s because they loved your personal touch. So trust your guts and don’t be afraid to experiment!

How can people connect with you?

Feel free to say hello through my socials @rainbow.shaker or via my website: Rainbow Shaker. I also have a brand new podcast channel, called Colour Your Home Happy!

justine guillermou colour your home happy podcast

Image source: #IDIstudent Justine Guillermou from @rainbow.shaker

Make Your Passion Your Career

Justine Guillermou’s journey from an aerospace engineer to a celebrated interior designer is a testament to the transformative power of following one’s passion. This story exemplifies how embracing a career pivot, fueled by the right education and a vibrant community, can open doors to new opportunities and personal fulfilment. Whether you’re looking to make a dramatic career change or enhance your existing design skills, The Interior Design Institute provides all the tools and support you need to succeed.

Through courses like the ones Justine undertook, which cover everything from basic design principles to Advanced Modules in tools like SketchUp and AutoCAD, IDI prepares you to tackle real-world challenges and make a mark in the design industry.

Are you ready to follow in the footsteps of success and turn your creative visions into reality? Enrol in our interior design courses at The Interior Design Institute and start your Interior Design career journey today.

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