Free Transform

  • Shortcut is CMD + T which gives the basic tool listed in the menu. This adds corner points to the selection which you can then move around with the Pointer to distort the image. 
  • Right clicking on this selection gives the other options as listed below. 
  • Drag the handles on the sides or corners to resize the selection. Holding down the SHIFT key keeps the proportion constant.
  • Dragging from outside the selection rotates the selection. Holding down SHIFT limits the rotation to 15 degree steps.
  • Press ENTER to confirm the selection, or ESCAPE to quit from it.

Transform

  • The Transform option listed in the menu lists the other options, which is the same as using Free Transform and right clicking on the selection. 
  • CMD + T gives a bounding box.
  • Can rotate from the corners, or even flip over the image.
  • CMD + DRAG will warp a corner out of square.
  • SHIFT + ALT warps corners to mirror each other if one corner is already selected. (Can’t get this to work)
  • CMD + ALT warps opposite corners as a parallelogram.

Other Options

  • Scale 
  • Rotate 
  • Skew 
  • Distort 
  • Perspective 
  • Warp 
  • Rotate 180º 
  • Rotate 90º clockwise 
  • Rotate 90º Counter Clockwise 
  • Flip Horizontal 
  • Flip Vertical

Links From