When working in a creative industry like interiors, it helps to operate in a space that sets the right tone. A drab grey room with poor lighting is unlikely to encourage your imagination!
As a designer, a good skill to practice is being observant of your surroundings. When you see something that sparks your imagination, just snap a photo or write a note. Taking inspiration from places other than the interior design world, such as the colour scheme from a street mural, is likely to result in more original designs.