How to make a background in this style?

Question

Design

The question is in the title. Subject. Without those dirty spots

Answer 1

Steps:
1. Create a new 10x10 document with a transparent background and draw a 5x5 black ellipse in the center.
2. Then create a texture (Edits - Define Pattern...). Now we have a pattern with dots.
3. Create a document of the size you need and fill the background with a gradient (Gradient tool - G) in the same way as in the example. (To create a gradient of the desired colors, obviously copy the colors with an eyedropper).
4. Create a rectangle on a new layer and rotate it (holding Shift) by 45 degrees. Then you create the same one and move it a little to the left (as in the picture).
5. Select layers with rectangles and create a smart object (On any of the selected layers, right-click - Convert to Smart Object)
6. In the resulting smart object, go to the layer properties and apply a gradient to it (the same as in the figure, blue-purple).
7. Create a new layer on top of all the others, remove the fill from it (Fill 0%), go to the layer properties and apply the pattern that we created at the very beginning. (Blending Options - Pattern Overlay)
All.