1. We will start by opening a new file; I made mine 100x100 pixels and filled it with black. Make a new layer.

2. Select the brush tool, , and pick the first brush from the default set - the 1px diameter brush. If you can't find the default set, then just click on "Reset Brushes" when you click on the brush tool.

3. I don't know about you, but most of the time I use white as the colour for my stars. However, it's absolutely fine to make your stars yellow, black, etc. So once you've picked a colour for your stars, go to the very top most right-hand corner of Adobe Photoshop. You'll see a tab that says "Brushes". Click on that, and check "Scattering". I've put it to the following settings:

4. Now draw all over your canvas. You'll need a steady hand and a good mouse (both of which I lack).

5. Go to Layer > Layer Style > Outer Glow, and keep the default settings.

6. Congratulations! You have just learned how to make sparkly stars. You can also do this with other brushes, and come out with something like this: