After 13 years cycling in the flatlands and winds of Manitoba ... my tips.
Ride easy into the wind. Don't push too hard. Spin as much as you can. Conserve your energy. Settle in and just ride.
Then, the moment the wind is blocked or it shifts slightly so that it is even a little bit behind you ... give it all you have. Ride like the wind! Take advantage of whatever small opportunity you've got to make some distance.