I have not done scrog so its pretty much the blind leading the blind.
You pull the shutes under the screen hole and force the shutes to go horizontally by tieing it to the screen, the shutes will grow back through the screen, let it grow for about 2" above the screen then weave it back through the screen hole and use ties to force the shutes to go horizontally.
You do this until the plant stops growing vertically.
If its your first time growing you should do a search and read up on scrog and maybe read up on growing in general.