Next step: stars. I thought that it it would be more romantic if the stars glow with horizontal and vertical rays. To do such star, switch to Shape tool (U), choose Polygon, set sides = 4, then open Options dropdown window, check Star, and set Indent sizes to 90-97%.
 
Rainbows - making of - Step 26
Add a shape (hold Shift to preserve proportions), then transform (Ctrl-T) to squeeze horizontally a little bit.
 
Rainbows - making of - Step 27
Next layer: wings (behind all layers of fairy). Made with Pen
tool! Apply same effects as to hair layer.
 
Rainbows - making of - Step 28
Set shape layer blend mode to Overlay, then in new layer, add a dot with white soft brush....
 
Rainbows - making of - Step 29
Ta-da! A fairy! the last step is to add one fairy for each color.

 
Rainbows - making of - Step 30
... then set its blend mode to Overlay too!
 
Rainbows - making of - Step 31
Add more stars in similar way.
 
Rainbows - making of - Step 32