Step 1: Create a new document of 1000px*1000px and fill the background with black.
Step 2: Create a new layer, fill it with white, and place it on top.
Step 3: Select the white layer, click Filter-Render-Fiber. Set the parameters according to the picture. (Difference 20, Strength 4).
Step 4: Click Filter-Blur-Motion Blur and set parameters according to the picture (angle-90, distance 999).
Step 5: Add "Gradient Overlay" to this layer. Remember to select "Overlay" for the blending mode and set the angle to 0.
Step 6: Right-click on the current layer and convert it to a smart object. Then copy a new layer and place it on top. Select the copied new layer, set the layer blending mode to "Overlay", and then click Filter -Other-high contrast preservation, radius 10.
Step 7: Click on the small eye in front of the background layer (black) to set it to invisible, then flatten the visible layers (shift+ctrl+E), and then change the size of the flattened layers as shown below:
Step 8: Rotate the layer to a 45-degree angle and stretch it to two opposite angles. Then click Image-Adjustments-Levels and set as follows
OK. The work is completed