Step 1
Before we start doing light effects, we need to create a light background. We can't simply use any background of our choice, but instead build a suitable canvas. Find a photo to use as your background (use a basic color palette, no retouching). It can be any image... just make sure it has lots of light and shadow.
Step 2
Here we need to apply a very strong Gaussian blur in PS. Go to Filter > Blur > Gaussian Blur and move the slider to a very high value. You can remove all the detail from your photo and have a mesh blur of all colors. I applied a Gaussian Blur of 75.
Step 3
Now we will completely change our background and add a Color Balance adjustment layer. To create this layer, go to Layer > New Adjustment Layer > Color Balance. This "New Layer" dialog box will pop up, just click OK. Next, you'll see 3 different sliders, representing 3 different ranges of choices (Shadows, Midtones, Highlights). At this point, you'll want to try moving the slider across each range until you find a suitable result. If you're using the image I provided, these are the values I set: Shadows: -37, -40, 7; Midtones: 15, 62, 0; Highlights: -34, 0, 69.
Step 4
That's the context of what we do. You can choose to edit your color balance layer later (just double-click the icon next to it), but now we're going to do the effects. First, select the Elliptical Marquee Tool from your toolbar. Make a large selection that covers both ends of the canvas. You may need to move the selection to do this. Then hold down the spacbar while dragging the mouse (don't let go of the left mouse button). You should end up with a slightly curved selection that covers most of the canvas. (To put it simply, it requires you to draw a super, super, super large oval selection box.)
Step 5
Create a new layer (above the adjustment layer) and use the Brush Tool from the toolbar. Select the default brush, then change the size to somewhere between 200-300 and set the hardness to 0. Choose white as your foreground color. This step may require some trial and error. But basically, you just paint the inside of the selection you just made. Try to paint the entire selection evenly.
