Going to windward in tough conditons:
Keep your speed up. This isn't always appreciated but speed is your friend because it provides the control to let you respond to conditions with the helm which is faster and more certain than easing the mainsheet which can snag or fail to release in a jam cleat. Controlling heel with the helm also points you briefly where you want to go so you'll spend less time out there struggling to get to your goal.
When the boat is overpowered, which it may often need to be in conditions where you have to carry enough sail to make good progress in the normal wind speed but have to deal with gusts that are significantly higher, sail by heel angle. Get the boat moving well in the lulls and then note the angle of the mast to the horizon or shore. Then steer to maintain that angle. Let the boat up easily, not to dramatically reduce the angle, but to maintain it. Don't worry too much about tell tales or luffing in such conditions. The harder you drive the boat (more heel angle) the faster the water flow over the rudder, the more control you will have, and the easier it will be able to hold the heel angle. Most modern designs have a critical heel angle at which you will lose control and the boat will round up quickly. You have to know where that is and not exceed it. Otherwise, resist the temptation to sail too gingerly. Once the boat starts to round up and heel decrease, you will need to quickly and firmly check the swing and hold her off.
If the distance to cover is not so great that you can accept the dramatically lower speed of sailing under main alone, it's a good option. It will not increase weather helm to an extent that makes most boats hard to control. The problem with the jib in very gusty conditions is that heading up too much, or heeling to the point where control is lost, can put the jib aback. The boat will then spin around on the other tack and you can be knocked down if you don't release the jib sheet fast enough. Eventually, you will know how to handle the boat well enough that this won't be a significant danger in all but the most gusty conditions.
Learn to reef the main and do it well before the boat is over powered. You'll be surprised at how much speed the boat often picks up when you reduce the size of the mainsail even though she didn't seem to be struggling.
There will always be times when you have to ease or even dump the mainsail. Always have the sheet clear and ready to do this. If you are depending on crew to handle the main and have the common cam cleat set up, be sure to instruct your crew to hold the sheet well back from the cleat and kick it out of the cleat with their foot.
You should quickly learn to anticipate when the big gusts are going to slam you hard enough to need to ease or even dump the main. Gusts are the faster moving air from aloft dipping down to the surface. They usually create turbulence, or even a vortex as the stream pushes down into the slower moving surface wind. When you feel a sudden brief lull and twitchiness in the wind, look out. More specifically, look to windward for that patch of dark water.
The gusts usually come from a slightly different direction than the normal wind. The greater the increase in gust speed, the greater the wind shift. The change in direction can contribute a lot to a knockdown. Once you know this, you can fairly quickly learn the gust direction and be headed up on the optimum course for the gust before hit hits and the increased heeling of the boat makes control more difficult.
