Do remember snacks and drinks in case of a break down.
Do bring a gallon of water with you. You may need some for your radiator or to wash of some mud or an injury.
Do secure everything in your vehicle that you don't want to get hit in the head with in case of a roll over. That tool box you brought "just in case" you break down is a great idea. But it could kill you if you roll over and it's not bolted down.
Do bring jumper cables. Splashing through deep water at a fast speed is a good way to sling a belt or fry your alternator. Jumper cables are a necessity.
Don't blind people with your lights if you are behind them. Light bars are all the craze right now, but they're bright as heck. Remember they are for off-roading purposes only and should only be used by the person in front.
Do remember to tell someone where you plan on
wheeling at before you go. This is very important if you do a lot of solo trail riding (which you really shouldn't do). If you broke down in the woods with no cell reception, how long would it take for someone to miss you and organize a search party or alert the authorities?
Don't forget to take it slow and enjoy yourself. Getting out in nature is a beautiful thing. Enjoy it. Go slow. Slow=safe, slow=ability to maintain control of your vehicle, slow=less cut tires, slow=less damage to your rig, slow=less likely hood of a roll over.
Don't get sideways on a hill. The majority of roll overs offroading occur when someone is climbing a steep hill, they lose traction and stop, they decide to "give it hell" and their rig ends up sideways and rolls down the hill. It happens all the time. It has happened to a friend of mine when we were wheeling at night. Remember if you lose traction going up a hill the best course of action is to slowly creep back down using your brakes. It's scary, it feels weird, but it's necessary. When you are stuck halfway up a long steep hill and lose traction completely gravity will take over. That means since the front of your vehicle is heavier, due to the engine, your vehicle will turn sideways as the front will try to beat the back to the bottom. When the vehicle gets sideways it can roll easily.
Allow vehicles that have not been re-geared to ride in front. Its going to be awfully frustrating following someone with a higher crawl ratio.
Pay attention to trail directions. Don't come down a trail the wrong way.. Its frustrating for everyone.
When stopping on a trail, NEVER cross in between vehicles, take the long way around, or crawl over.
A fellow driver lost his life when he crossed between vehicles, and got pinned in, from the uphill vehicle slipping out of gear.