1. You can go to Lego.com and go to customer service and to
'building instructions' then write the product number (like 10131)
then enter it.
2.When you see the product name in the bottom of the page, you
can click it again.
3.Then you will see the product image and 'download' sign. Click
it by RIGHT side of the mouse and click 'save to', then save where
you want.
4.Maybe it will take a bit of time. And when it is done, go to
the place you saved the instruction then click that and there it
is!