To make an odd-shaped selection such as an archway or pear, start with the Shapes selection tool. For an archway, you begin with a rectangle selection, then simply add a Circle selection top. To do this, hold down the Shift key while you add to the selection. Click and drag from the top-center of the rectangle to the edges of the rectangle selection, then release the mouse button. You've just added to your selection. To subtract from a selection, hold down the Ctrl key while making the selection.