Mast all the way out, down haul off.

But do NOT let the main sheet go slack, keep it pretty snug, it is the backstay and it is the only thing working against the pull of the spinnaker halyard to keep the mast from snapping under the spin loads.

The apparent wind should be about 90 degrees off the bow so the main can stay sheeted in and fairly flat, ease the traveler down a foot or two, more if it’s really blowing and way out just before you jibe, but do not let the main sheet get slack when the spin is up and pulling.