Simple brightening tutorial
Going from this
to this 
Grab your image and crop it to the LJ standard of 100x100. I got the picture from here, cropped it and ended up with this, all sharpened and ready to go. Note, I went Filter > Sharpen > Sharpen Edges, but you can sharpen it the old-fashioned way, if you want.
Next, I duplicated my base 3 times:
I set my first copy (the one right above my base aka "Layer 0") to Screen, my second copy (middle layer) to Soft Light and the copy at the very top to Pin Light.
You get this and you're done! Simple, see?
Now, you can leave it at that or add a bit more like I did since I feels it's lacking a little something. For this, I'm going to use text, but you can go ahead and use whatever brush or anything you want; I just suggest not making it anything too "bold" or "bright".
I used "Bookman Old Style" for the font, colored white with a size of 5 pt. I then lowered the Opacity of the text to 50%, but you can play around with the opacity to your liking. Like I said, I just suggest not making it too "bright" since I feel it overpowers the image in a way.
the end.
