As usual, start by opening your image in Photoshop
Go to Image > Adjustments > Levels,
Level window will pop up
Channel Drop Menu, this allows you to choose whether your changes should effect all the colors, or just one (red, green, or blue).
Input Levels: Black is for shadow, gray for midtones and white is for highlights.
Make sure the Preview box is checked on, so that you can preview the picture as you make changes.
Choose the channel you wish to change and drag the triangles. Dragging black triangle to the right will make the shadows in your photo darker. Dragging the white triangle to the left will make the highlights in your photo lighter, and dragging it to the right will make the midtones darker. You will be able to see the changes in your image
Here is my Photo after editing
