The work related to installing windows it is good to ask the company in which window were purchased. Specialists know better how to mount the window to serve them without problems for many years. Is worth have in mind that poorly mounted window will be difficult to use. The instant having problems during opening and closing.
At the beginning the installed frames. It should be good prepared hole in the wall, clean it. After the initial installation, mount the wings. Previously created frame should be secured so as not to tear off during operation or soiling of the foam. From inside window should be sealed with silicone.