You obviously want to make sure you have some form of caravan stabiliser fitted and your caravan is within weight and loaded properly. However, if your caravan is swaying or snaking, there are means to counter it. First, don't panic and don't start to significantly move the wheel from left to right to try and correct the snaking. Furthermore, don't try and accelerate out of it or slam on the breaks. Keep a medium grip on the steering wheel straight ahead. Ease off the accelerator and 'calmly' wait for the snaking to correct itself.