Lean into the wind.
Headwinds aren't too bad...
it's sidewinds that make life interesting - you end up with the bike cranked over like you're cornering just to travel in a straight line.
And what will really mess you up is when the wind gusts. First you get pushed across the road from the unexpected wind, then you
lean into the wind to correct and when the gust finishes, you travel sideways across the road in the other direction as you're now leaning too hard!
I did a dirtbike tour in cambodia.. and we were riding through a storm at one point and everytime the wind gusted we were getting pushed
about 10 feet sideways. Not much fun when there's oncoming traffic and no centre divider.
If it's seriously hurricane force you're probably better off pulling over and taking shelter somewhere.
One sideways gust strong enough to throw you in front of a truck can ruin you day.
I rode in the wind storm produced by Katrina. It was no hurricane force but it was strong enough that I had the bike pretty well cranked over to go straight. I've gotten pretty good at keeping the bike in the same place even with unpredictable blasts. As stated already, if you're really getting hammered, it's probably best to just stop. And you might as well go ahead and lay your bike on its side
Another thing that you have to watch out for is changing direction into or away from the wind. I was test riding a bike once with a pretty steady 30 mph crosswind. After about 5 miles or so of this wind pushing me from the right I went to turn around (to the left) and nearly fell over from the decrease in wind pressure! I hate to think what would have happend had a Semi come passed while I was riding.