Why not do a Google search for make and model of sectional door you have. There may well be installation instructions you can download.
here's a couple of makes I found:
http://www.hormann.co.uk/products/garage-doors/sectional-garage-doors/
http://www.teckentrup.co.uk/products/carteck-garage-doors/sectional-garage-doors/
https://www.garador.co.uk/garador-range/sectional-doors.aspx
XXX
April 2016