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Change the red color to #FFC00 (you still have 75px brush selected) and brush the layer on the inside of the red shape (still remain on the same layer)
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Repeat same step but change color to #FFFFFF
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Now go to Filter > Blur > Gaussian Blur and apply the radius to 45px
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Create a new layer (Shift +Control + N) reset the color (press D) and go to filter > Render > Clouds. Next, press Control + F about 2 times to repeat the filter. Then, change the blending mode of the layer you just made to Color Dodge.
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Go to Layer > New adjustment layer > Levels and press OK without changing the parameters.
Next were going to make a very easy start. Make a new layer (Control + Shift + N) and fill it with black. Go to Filter > Noise > add noise. Amount : 14, Distribution : Gaussian, Monochromatic : Turn ON. When you done doing this. Change the blending mode to screen
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Lower the opacity of 'supernova' layer. then make a new layer, fill it with black. Go to Filter > Render > Lensflare. adjust the lens effect. after it done. change the blending mode to screen and you've done in making a supernova!
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