Adobe Photoshop CS4 Keys for using the keyboard shortcuts keys

Shortcut                                                                         Command
Cmnd-click layer thumbnail	Load layer transparency as a selection
Cmnd-click filter mask thumbnail	Load filter mask as a selection
Cmnd + G	Group layers
Cmnd-Shft + G	Ungroup layers
Cmnd-Optn + G	Create/release clipping mask
Cmnd + Optn + A	Select all layers
Cmnd + Shft + E	Merge visible layers
Optn-click New Layer button	Create new empty layer with dialog box
Cmnd-click New Layer button	Create new layer below target layer
Optn + . (period)	Select top layer
Optn + , (comma)	Select bottom layer
Shft + Optn + [ or ]	Add to layer selection in Layers panel
Optn + [ or ]	Select next layer down/up
Cmnd + [ or ]	Move target layer down/up
Cmnd + Shft + Optn + E	Merge a copy of all visible layers into target layer
Highlight the layers you want to merge, then Cmnd + E	Merge layers
Cmnd + Shft + [ or ]	Move layer to bottom or top
Optn + Merge Down cmnd from the Panel pop*'up menu	Copy current layer to layer below
Optn + Merge Visible cmnd from the Panel pop*'up menu	Merge all visible layers to a new layer above the currently selected layer
Ctrl-click the eye icon	Show/hide this layer/layer group only or all layers/layer groups
Optn-click the eye icon	Show/hide all other currently visible layers
/ (forward slash)	Toggle lock transparency for target layer, or last applied lock
Double-click layer effect/style	Edit layer effect/style, options
Optn-double-click layer effect/style	Hide layer effect/style
Double-click layer	Edit layer style
Shft-click vector mask thumbnail	Disable/enable vector mask
Double-click layer mask thumbnail	Open Layer Mask Display Options dialog box
Shft-click layer mask thumbnail	Toggle layer mask on/off
Shft-click filter mask thumbnail	Toggle filter mask on/off
Optn-click layer mask thumbnail	Toggle between layer mask/composite image
Optn-click filter mask thumbnail	Toggle between filter mask/composite image
\ (backslash), or Shft + Optn-click	Toggle rubylith mode for layer mask on/off
Double-click type layer thumbnail	Select all type; temporarily select Type tool
Optn-click the line dividing two layers	Create a clipping mask
Double-click the layer name	Rename layer
Double-click the filter effect	Edit filter settings
Double-click the Filter Blending icon	Edit the Filter Blending options
Cmnd-click New Layer Set button	Create new layer set below current layer/layer set
Optn-click New Layer Set button	Create new layer set with dialog box
Optn-click Add Layer Mask button	Create layer mask that hides all/selection
Cmnd-click Add Layer Mask button	Create vector mask that reveals all/path area
Cmnd + Optn-click Add Layer Mask button	Create vector mask that hides all or displays path area
Ctrl-click the layer group and choose Group Properties, or double-click group	Display layer group properties
Shft-click	Select/deselect multiple contiguous layers
Cmnd-click	Select/deselect multiple discontiguous layers