hey sascha, thanks for the comment, the basic techniques i used was the brush palette so create the dots, i just set the spacing high as well as the scatter, i also adjusted the size jitter so it created some bigger and smaller dots but not too small.
As far as the colours go i just selected differant colours each time and started brushing around. I made a fair while ago and i have misplaced the .psd file so i cant exactly remember the steps. I'm pretty sure i set the blending mode to either Overlay, Darken, Screen... you will just have to test the blending options to see what looks good..

Again thanks for the comment

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