Set the appropriate parameters!

The highlight effect can be done directly with the white brush and smudge tool!

1, create a new layer, draw a little white with a brush, and then disperse the white with Gaussian blur; You can also use a lighter color than your background!

2. Create a new layer, fill it with black, adjust the transparency by about 20%, use a white brush (reduce the transparency), and paint the part that needs to shine with white. The more brightness, the less brightness, and then adjust the blending attribute of the layer to lighter color;

The first method is recommended, which looks more natural, and the latter is suitable for highlight processing when hand-drawing!