I’ve come across more than a few handfuls of people stuck in their four wheel drive, with zero recovery equipment (and often zero knowledge of what to do too!). I don’t say this to be discouraging, but it is vital to be prepared when you go four wheel driving. If you take the time to learn the basics of four wheel driving, and you get the basic recovery gear you will have a safe, and very enjoyable time every time you head out. I always suggest going 4×4 with two vehicles, to make it safer and easier to recover one if you get stuck.
However, there are a few things that you should always have in your four wheel drive, regardless of where you are going. The first is a shovel. A few minutes digging around your tyres will usually make all the difference when it comes to a four wheel drive recovery. The second is a tyre gauge. When you go four wheel driving tyre pressures should be dropped according to the terrain, to allow for a greater level of traction. If you can’t tell what pressure your tyres are at, you are in big trouble! The third is a compressor, which is required to pump your tyres back up to their normal level when you are finished four wheel driving.
If you are driving on bitumen with under inflated tyres you can easily damage them, and they aren’t cheap! Fourthly, make sure you have at least one rated recovery point on the front and rear of your vehicle. This means that if you get stuck you can be safely pulled out from both directions (whichever is the easiest). Tow balls are not to be recovered off. Many people have been killed by recovering off tow balls, as they have a history of breaking and creating very nasty flying objects.
I also recommend carrying a Snatch Strap, but only if you know how to use one safely. This includes using a dampener, attaching it correctly to rated recovery points and towing correctly with it. Snatch Straps have injured more than a few people; please use them safely! I also recommend a product known as Maxtrax, which are engineer grade nylon tracks, designed to drive onto. These work incredibly quickly and safely, and they don’t put anyone at risk by building up kinetic energy (like Snatch Straps do). If you have never been four wheel driving, its worth doing a short course to learn the basics.