Step three:

Create a new layer.

Go to Select > Load select > Default to select the entire skittle.

Nudge the selection two times to the left and bottom. Tap the arrow keys twice =)

Grab the brush tool with a foreground color of #FFFFFF, brush the tip lightly to add a gloss effect.

Step four:

Create a new layer.

Change your brush size to something small like a soft 5 px brush. Since the gloss is located at the top of the skittle, the perspective is looking like the skittle is leaning on another skittle. Add a dot on the bottom, across from the gloss.

Change the opacity level of the dot to 33%.

Step five:

Add the letter s to the skittle. My font settings are Arial, Bold, 26 pt, Strong, #FFFFFF.

Rotate the s to right by going to Edit > Transform > Rotate.