Instructions
Open an image-editing program on your computer. Programs which come with your computer by default, such as "Paint," normally don't have the ability to manipulate photos in the required way. There are several paid options, such as Photoshop or Paintshop Pro, which will be suitable.
Open your photo within the image-editing program.
Select "Hue/Saturation." Within Photoshop, this can be found by selecting "Image -- Adjustments."
Increase the level of saturation until you achieve the desired effect.
Press "OK" and save the photo.