Spears are an ideal way to defend yourself if you don't have such a steady hand for a bow and are not willing to get close enough to use a knife. They also make it safer to engage in a heated conflict. You can make regular spears by just sharpening the top of any long stick preferably about a foot taller than yourself. Such lengths gives you more distance away from whatever is attacking you or what you are attacking. Making multiple spears is a good idea if you're looking to defend yourself. Just spread the spears in the ground around where you're sleeping and if any animal decides that they want to take a bite out of you it will get poked by a spear. If you are looking for something a little more deadlier attaching a rock that has been chipped away to be sharp should do just fine. If you are hunting for fish or aquatic creatures you can use regularly sharpened spears and split the top of it down the middle. Then cross it again to make an axe through the center of the spear about 6 - 9 inches wide. Then get small twigs and some leaves and jam them down the center of the stick, so the four prongs spread out and give you a bigger area to use. If you are not looking to really jab or seriously injure an animal you could attach a big rock to the top of the spear and swing it around as defense. The key when using a spear is the closer to the top you hold it the more control you have but, the farther back you hold it, the more leverage you have.