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.
When you use the Magic Wand tool you have the option to set the tolerance, which determines the range of pixels selected when you use the tool. But did you know that the tolerance setting for the Magic Wand tool can produce different results depending on how you have the Eyedropper tool's Sample Size option set? This option determines the number of pixels both tools sample.