Let's go to draw a lighting rays background.
New File: Take a new file with any size as you like.
Take color: First take background and foreground color.
Fill color: Fill color by the Paint bucket tool (G key) in the layer.
Noise: Go to Filter menu > Noise >Apply Add noise and make similar setting.
You will get it.
Motion blur: Go to Filter menu > Blur >Apply Motion Blur.
Modify design size: Press Ctrl + T and right click then choose "Skew" to modify the shape.
Gaussian blur: Go to Filter menu > Blur >Apply Gaussian blur.
Level: Go to Image menu >Adjustment >Apply Level.
Bri/Cont: Go to Image menu > Adjustment >Apply Brightness/Contrast.
You should have similar picture.
Lighting effect: Go to Filter menu > Render >Apply Lighting effect.
This is your final result.
Recommend the tutorial