Quick Key Commands

Command + Shift + I (Invert Selection)
Option + Delete (Fill Foreground Color)
Command + Delete (Fill Background Color)
Command + Shift + <> (Change Text Size) Text must be selected
Option + Arrows (Change horizontal and vertical space between text)
Command + ' (Grid On and Off)
Command + R (Rulers)
MAC Shift + Option + (+ or -) (Toggle Through Blending Modes)
PC Shift + Alt + (+ or -) (Toggle Through Blending Modes)

Command + G (Group)