I know this incredible simple technique which produces such a nice outcome, that may come very handy to a lot of beginner designers. You can barely call it a tutorial, but it's weird that some designers haven't discovered this simple yet very effective quick method which can add an extra beautiful touch to your work.
Program: Adobe Photoshop
Difficulty: Incredibly easy
Time: 15 minutes
Here we go.
To illustrate and explain the effect I've been talking about I started with opening a simple stock picture from sxc.hu from a cool BMX stunt in Photoshop (CS). You can use any kind of picture to try this tutorial and discover the simple light effect.
The next challenge is to go out there and find a decent stock picture with some kind of dynamic light effect on dark background. I came across this picture of someone playing with a torch taken with the long-shutter photographic technique that gives this nice sparkling effect.
When you've found your image, place it into your file and think about what you can do with it. Of course knowing the technique is one thing, using it creatively is another. Make sure the light effect picture is in a new layer above the background layer.
Once you've figured out what you want to do with your light effects, we can finally go to the most important part of the tutorial. Put the blending mode of the light effect layer on "Lighter" or "Screen" in the layer palette. Magically the dark background disappears and the nice light effect stays. That's basically what those two filters do. They maintain the bright colors in the image and make the dark colors disappear. You need to switch to "Lighten" and "Screen" a couple of times to see what fits best with your idea and your background picture.
Now that you know this incredibly simple technique, all what's left is to be creative with it. I started with playing around with the "erase tool" to get rid of those image borders. In the picture above you can easily see where the effect stops. Thanks to the erase tool and a soft brush selected and can manually create a smooth transition between the light effect and the background.
In this step I basically duplicated the light effect layer and put it into place so it fits with my idea.
Thanks to the Hue / Saturation window you can modify the colors very fast and very easily. Select the light effect layer, go to image - adjustments - hue/saturation and play around with the options to get the color you like.
I have erased the tires to finish my simple concept after I did some color corrections with the "curves" tool (image - adjustments -curves).
This technique is very fast and very simple, but the downside is that you're limited to the stock pictures available. To become completely free you need to learn to draw your own light effects. Something that might get explained in a new tutorial.
I've made an artwork a while back using this technique. This is just to show you how creative you can be using this sort of blending.