In this great Adobe Photoshop tutorial you will see the basics of making custom brush presets, to make glowing stars effects.

1.
Start by selecting the brush tool, select the color white, then go to the custom brush panel, (default located at the top right corner).
Give it a brush tip shape as in the image below.

2.
Now in the scattering panel give it settings as in the image below.

3.
The last thing in the custom brush panel is to give it shape dynamics

4.
make an empty layer to draw in, double click the layer in the layers panel to get to the layers style panel, give it an outer glow as in the image below.

5.
Now you are ready to draw, so , then make your brush quite big and draw a line over the scene as shown below, after drawing a couple of stars, make your brush a bit smaller and draw some more.

6.
In the layers panel, make a new layer, then hold down shift and alt keys and drag the small f (layer styles) from the first star layer onto the new layer, so you have copied the styles.
Double click the new layer and go to the outer glow style, change only the color (I changed it from yellow to blur).

7.
Now draw some lines in the new layer, they should appear with a blur glow as shown below.

8.
Make new layers repeat step 4-7 and change the outer glow colors a couple of times and you will end up with a result like mine.