This tool is popular amongst engravers and designers who want quickly develop, balance and enhance textures and designs.

Selecting motifs is very simple. Similar to the  Carbon Copy Tool, you hold down ⌥ (option key) to select the area you want to stamp throughout your design. Selections can be made in rectangles, ovals, by using a lasso, or by using current brush (setting your current paintbrush as a stamp). Once a selection has been made, the selected motif can be resized using the 1 and 2 keys, and rotated as you work using the 3 and 4 keys. Each click of the 3 and 4 keys rotates the angle by 1º. All resizing and changes made to the angle of the stamp can be reset by pressing 0 on your keyboard.

For anyone who is left handed, the [ and ] keys can be used to resize the motif, and the left and right arrow keys can be used to rotate.

• Drag from centre - your selections will be drawn from their centre point as opposed to the top left
• Snap to selection - snaps your selection to the content within the selection. This option is on by default
• Set Source From Current Selection - sets any existing selection in the document as your stamp motif
• Add stamp to Brushes - will add your current stamp into the Brushes library
  
  

The movie below shows you everything you need to know.