Step six:

Create a new layer.

Lets add shadows to the skittle by drawing a flat #000000 oval with the ellipse tool under the skittle.

Go to Filter > Blur > Gaussian blur. No settings will be provided since your shadow could be bigger or smaller than mine but when adding the filter make sure the blur is not bigger than the skittle itself.

Step seven:

Finish the skittle off with sour sprinkles. First select this brush from your brush set. The brush is default on Photoshop 7.0.

Create a new layer

With a foreground color of #FFFFFF paint the brush once on the skittle. Erase the extra paint outside the skittle.

Go to Filter > Sharpen > Sharpen more.

Set the blending mode to Overlay.

Finale:

You learned the technique, use it to make the rest of the colors.