Image editing with multiple layers presents some navigational challenges. Sometimes you select the wrong layer, or sometimes you simply want to cycle through the layers panel selecting different layers. It’s easy to select different layers with the keyboard instead of the mouse, saving yourself some time and aggravation. First, see what layer you have selected in the Layers panel. To select the layer above, press [option][ ] ]([Alt][ ] ] in Windows). To select the layer below, press [option][ [ ]([Alt][ [ ] in Windows). For either direction, if you continue pressing the bracket key while holding the modifier, Photoshop will cycle through the layers.
Select the Dodge or Burn tool from the Tools panel. Press [ [ ] to decrease the brush size, and press [ ] ] to increase the brush size.
To edit the Exposure, you don’t need to highlight the text field on the tool Options bar, simply enter a value on the keyboard from 0-100. For a value of 1-9 percent, enter values as two digits, such as “02” for 2 percent.
To select which range you wish to target, press [shift][option]S ([Shift][Alt]S in Windows) to select Shadows, press [shift][option]M ([Shift][Alt]M in Windows) to choose Midtones, or press [shift][option]H ([Shift][Alt]H in Windows) to select Highlights.