There are many ways to fix the contrast levels of your pictures but I'm going to show you two simple methods including my own method of fixing/applying contrast to images. I mainly do this to my car pictures but occasionally I do this on my portraits and my flower/nature pictures. Feel free to experiment and see what works for you and hopefully these methods will work for you.
So here we have our stock image. As always, I try to get a good exposure that is balanced in all areas so I don't have to heavily edit/fix in post. I'm using Photoshop so for those of you using any other image editing software, hopefully you could match these settings/actions.
Applying the usual brightness/contrast adjustment you could see that the blacks/shadows and colors are brought out more and that white haze you see from the stock image is minimized. You could do this by going to image>adjustments>brightness/contrast. From there you could set the brightness and contrast levels to your liking.
Here's my method of applying contrast. I don't like to exaggerate colors if there isn't much contrast between the subject, lighting, and background. I added a gradient map via adjustment layer panel. You can do this by going to Layer>New Adjustment Layer>Gradient Map. I usually use black to white but depending on your image, you'll have to find the right amount of contrast between black and white; exploring other settings doesn't hurt either. XD
It's always up to personal preference on how you want the image to turn out. Keep in mind though that if you stack on effect after effect on a single layer and you find that your picture is looking ugly or not to your liking, you probably won't be able to backtrack and go back to where you want to start over; in other words, work in layers. Also, don't expect to save your image if it was crappy to begin with. Spend time and adjust your camera so that you can take a balanced exposure. Don't be afraid to review and check your picture, and when in doubt, check the histogram.
Hopefully this tutorial helped. For those of you who are getting into photography or who are lost whenever they want to post edit, here's a little start to fixing your pictures. Anyways, stay tuned for more tutorials in the future and be sure to like the facebook page!