Drag an empty area to draw a panel. Drag a panel to move it; drag any of its four corner handles to resize. The blue panel and highlighted list entry show your selection. Hold and drag a panel in the right-hand list to change reading order. Scroll to zoom; hold Space and drag (or use the middle mouse button) to pan. New panels go after the selected panel. Supr/Delete removes the selection; Ctrl+Z undoes and Ctrl+Shift+Z redoes.