Pepakura Designer is mainly operated by your mouse. A mouse with a wheel enables easier operation of the software. If your mouse doesn't have a wheel, a combination of keyboard and mouse allows you the same operation as a mouse with a wheel.
The functions on the screens of the 3D model window and 2D pattern window are as follows. Learn them in order to work smoothly and efficiently. Since this description of the operations is shown on the status bar, it will be helpful to you.