Steps to create Halo Effect

Following are the steps to create a Halo effect using Photoshop

Step 1
Take a new file (Shortcut Ctrl + N) in Photoshop. Paste a picture on which you want halo effect. Use an image which is not too big or adjust its size.

Step 2
Select the Magic Lasso tool from the toolbar and select the background. Your image will look like this after selection.

Step 3
Click on Select > Modify > Smooth from the menu. Give a smoothness from 2 to 4.

Step 4
Next click on Filter > Artistic > Neon Glow, the neon glow window will appear like the one on the right.

Play around with the settings till your glow seems fine and click on OK.

Step 5
Here's the image with a halo.