Soft Pastels are interesting media to work with. It can also be fun for you can use your own fingers to apply the color or you can use a brush or cotton balls.Just outline the drawing with your chosen color and smudge it with your finger, brush or cotton. You can achieve a soft, hazy look with this just like the one in the picture. Plus, you can actually erase smudges using eraser.
Always Color in a Consistent Direction. This is my first tip. It will make a bigger impact on the end result than anything else and any age can use it! The changes in direction, shown on the red kidney below, on the left side, are what make it look sloppy, even though I carefully stayed in the lines. Coloring in a consistent direction, as seen on the other kidney, is easier on the eyes and ends up looking very tidy!