Starburst Effect

Step 1: Select a Gardient tool and then press a Reflected Gradient button:

Step 2: Then make a gradient of your choice:

Step 3: Go to Filter > Pixelate > Mosaic:

Step 4: Then set these options:

Step 5: Go to Filter > Distort > Polar Coordinates:

Step 6: Set these options:

Step 7: Now it should look like this:

Your Starburst is finished.