Women can see more shades of red and orange than men. The gene that allows women to see red is the X chromosome. Because women have two of these X chromosomes, it gives them more colour variation in the red-orange spectrum. Women have two of the genes and men only have one. This means that women are able to see so many different shades of red and orange and men can only see a few. Where women can see crimson, maroon, cardinal, ruby, and scarlet, men might only be able to see light, medium, and dark red.

The national bird of Honduras, Scarlet Macaw is one of the most beautiful birds found in the tropical rainforest. They are known for their beautiful bright plumage. They are also curious, strong willed and highly trainable in captivity. The feathers of the bird are red, blue and yellow and the area around the eyes is white. The upper portion of the beak is white and the lower half is black. What distinguishes the Scarlet Macaw from other Macaws are its bright feathers. This helps them to blend into their natural habitat in the rainforest.

Impossible colours, also called forbidden colours, are colours that are too complex for the human eye. Your eyes can't perceive these colours because of the way they work. Basically, the human eye has three types of cone cells: Blue versus Yellow, Red versus Green and Light versus Dark. There is always an overlap between the wavelengths of light covered by the cone cells, so you see more than just blue, yellow, red, and green. Because of the opponent process, you can't see blue and yellow or red and green at the same time. Impossible colours like reddish green or yellowish blue are trickier to see.

Get inspired from various elements.
It is one of the easiest ways to choose interior paint colour. Throw pillows, bedding, and even table linens can provide you with paint colour ideas. If you're creating an accent wall, look for the boldest colour in the print. Want to choose a paint colour that is more subtle or for a larger space? Look at the colour in the tiny details of your print fabric. If you've got patterned upholstery, a colourful rug or large piece of artwork, pluck colours you like from the pattern.

Try a light to dark shade combination.
Sometimes all you need is a little adjustment to find the right interior paint colour. Consider a lighter or darker shade of the same colour. Many paint colours appear on a paint strip in gradual shades, but you can also ask your paint store to customize it by percentages of light or dark shades. Use darker colours on the floor, medium colours on the walls and lighter ones on the ceiling. Designer Mark McCauley says "Any interior space replicates the outside world. The exterior environment is generally darker below our feet (the earth), medium-valued as you look straight ahead (buildings/trees) and lighter skys."

Begin with the formal areas first.
Specifically, the living room and dining room. Choose a colour scheme for those areas first, then pull one colour from the scheme and use elements on the other rooms. Don’t forget to use the rule of 60-30-10. When decorating a space, divide the colours in the space into components of 60 percent of a dominant colour, 30 percent of a secondary colour and 10 percent of an accent colour. The walls will be the majority, the upholstery would represent the secondary colour and other accessories would make up the rest.