Hafren is another easy stage. The only problem you might find with this stage is that your car is wrecked - the only way to avoid this is practice, practice and more practice. If you didn't change your tyres earlier, you'll find that wheelspins throughout this stage will destroy your gearbox. The wet gravel tyres help to save the gearbox a bit as will not hitting anything.
The stage itself is the first snow stage of the rally and brings slightly different handling into play. To control the car through the snow covered bends hold down the brake whilst turning. This should stop the back end of the car sliding out too much. Apart from a few suspiciously well-placed trees you should only really think about hitting the brakes when a small stone wall appears on your left near the end of the stage. It is here that the road becomes much more twisty and suddenly littered with logs.