relax and if the bike needs to move, then let it move.
give yourself lots of room on the down wind side to allow the bike to move if it needs to.
And slow down to a snails pace if you need to
Last years Grand Challenge I rode SH16 from Wellsford to Auckland in 140kph cross winds (as many others here did) .. I didn't die

RELAX, I rode at 80-90kph the entire way, and caught people up ...
Keep an eye on the surroundings, prepare yourself for breaks in the hillsides on the road side, or large shelter belt trees are another thing, when they break, like for a driveway, you will get sudden gusts.
be prepare to turn harder in some corners ... if the wind get under your bike on the inside of a corner, it may be less than willing to lean over, so prepare .. be ready to countersteer harder.