Step 1: Open the picture you want to practice with, in this tutorial I use the picture below

You can get the original image here which is in a very high resolution

Firstly, we need to adjust its brightness and contrast, so go to Image > Adjustments > Brightness/Contrast and use these settings:

Step 2: Go to Select > Color Range and click on a white area of this picture to sample it

Click OK when the girl is covered with black. Make sure to remove all the selections on the girl with the marquee Tool (you should use Subtract from Selection option to remove them). Here is our picture after this step:

Step 3: Press Ctrl-J to duplicate the selected areas. Go to Filter > Blur > Radial Blur and use these settings:

Step 4: Press Ctrl-I to invert this layer's color. Now we had a nice background ^_^

Step 5: Now press Ctrl and left click on the current layer (it is Layer 1 by default) to load the selection areas again. Create a new layer, we are going to draw a nice rainbow! Here is our Layers tab at this time

Step 6: Use the Gradient Tool (G) with Radial Gradient and Russell's Rainbow options. If you don't know how to get these options, follow the images below:

Now draw a line from the center to the corner to get a nice rainbow 

Step 7: Use the Eraser Tool (E) with a soft brush to erase unwanted areas if your picture has. Remember that you have to select Layer 1 as your current layer

Step 8: Make sure you are on the Layer 1. Double click on this layer to open the Layer Style dialog box. We will use Outer Glow with a big size for this tutorial

Step 9: Press Ctrl-B to open up the Color Balance dialog box. We just need to use Highlights option

Use the Brush Tool (B) to add some nice shapes if you like. Here is the final result:

Now you can add your text and some information on this picture. I hope you enjoy this tutorial!

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