Tap， tap 'Handcraft'，draw the polygon selection of the head。Use 'Max zoom' to zoom in if necessary。Tap OK to connect the last edge of the polygon and complete the editing.
While the polygon is selected, tap 'Image stamp' button，this will copy the image of the polygon as an image stamp
Enlarge/shrink 'image stamp'，adjust position. Adjust 'smooth border' to make the head natural。One of the two dog heads in the example is generated by cloning and flipping. Select a image stamp, Tap 'Image stamp' button to clone the image stamp. Click 'any angle' to rotate the image stamp.
If a polygon is already converted to an image stamp, and you want to edit the control points. Tap the button of the image stamp settings. When you tap the button, tap the 'arrow' of the toolbar to switch to zoom mode(+magnifying glass). In this way, when you tap the screen, the polygon doesn't disappear immediately.