1. Click on the white box. You will then be brought to a colour spectrum. You can adjust the arrows on the colour spectrum to pick a colour that you are happy with or fill in the exact HTML colour code that you want.
2. Once you are happy with the colour, click on the spectrum circle on the lower right side of the box.
3. You can then preview the changes you have made which will appear above the colour bars.
4. When you are happy with the colours of your poll, click on Save.