If you spend a lot of time in the great outdoors and also hike and walk regularly, then it may be useful to take a wilderness training course. These courses teach you bush craft and survival skills for treks and walks in a variety of environments.
You can choose from an array of courses, from a short one day awareness course to a five day immersion course. Techniques you can expect to learn are fire lighting, how to pack equipment, open fire cooking, whilst survival skills taught range from wild food gathering, shelter building, rescue techniques through to how to improvise transportation of casualties.
Make sure you have enough food for energy, such as dried fruit, an energy bar or trail mix. If you injure a limb, it is best to cut your walk or hike short as an injury can be exacerbated by putting extra pressure on it on rough terrain. Carry a torch with you always, even if you set out in the day, as well as carrying a secondary light source such as snap lights or a wind up torch, in case your batteries run down.
Most importantly, always make sure that someone is aware of where you are going and when you plan to be back, in case of any emergencies, your designated contact knows where you were planning to go.