As with all processing, your personal taste counts for something. This tutorial is set up to allow you to tweak to your heart's content. This process is not meant to be a one-size-fits-all tute, rather some insight into different ways to play around with your image. This tutorial also assumes you have a good understanding of Photoshop.
First, you'll need to start with a well-lit image.
With the top (dark) curves adjustment layer selected and your foreground color set to black, use a soft brush (0% hardness) at a low opacity (around 20%) to paint over any place that has gotten too dark.
Mask this layer and paint away any part of the image that has gotten too dark, using a soft brush (0% hardness) with low opacity (20%).
You can choose to stop here or continue to tweak the adjustment layers until you’re happy with the result. Or you can take things a few steps further to make this extra crispy.
Add a mask to the top layer, then invert it (Cmd/Ctrl + I).
Select the paint bucket tool, set to 30% opacity, and fill the mask with white. This will give everything a slight blur.
Use the brush tool (0% hardness and 20% opacity) and paint onto the mask with black to bring back sharp details or paint with white to blur areas more.