Many people think that if they just have this one tool, or the right gun, or a super-secret hide out, they can survive anything. They are wrong.

The thing about survival, whether it means walking 100 miles through the Amazon back to civilization, persevering after a natural disaster, or fighting off the hoards of imaginary zombies that are never coming, the most common attribute of those who survive is creative thinking—improvising to accomplish the necessary tasks. In a survival situation, you won’t have the luxury of driving to your local supermarket or hardware store, so you need to learn how to work with what you’ve got before the time comes.

In a survival situation, you’ll usually either have a disposable water bottle or a Nalgene bottle on hand, or you’ll likely be able to find a disposable water bottle because of thoughtless litterers who have passed through the area before you. Thanks to the curve of the bottle and refraction from the water, you can focus sunlight into a beam capable of igniting tinder to start a fire. It’s not as intense as the beam you’ll get from a true magnifying lens, but it’s better than nothing.

I recommend storing as much food as space allows, but true sustainability can only be achieved by growing your own food. Using old toilet paper tubes filled with soil is a great way to get your seeds started in an easily controlled environment, and once the sprouts get large enough to move outdoors, you can simply place the tubes into holes in the ground. The cardboard will disintegrate, and the roots will grow down through the open bottom.

The packaging that rice and beans come in is porous and easily torn which reduces the shelf life of your valuable food. A better alternative is to transfer these dry goods into 2–liter soda bottles, which are made from much thicker plastic and offer an air-tight seal. If like my family, you don’t drink soda, you can probably get more than enough bottles from friends. You can ensure an even greater shelf-life by adding an oxygen absorber to each bottle.

You can use AAA batteries in place of AA batteries by simply balling up some aluminum foil to fill the gap in the battery compartment. Both types of batteries output 1.5 volts and differ only in amperage (AA batteries produce a little more than twice the amps than AAA batteries do) but in a device like a weather radio or flashlight, this isn’t something to worry about.

I think we can all find an empty beer (or soda) can lying around, and when combined with a candle, we have a handy improvised lantern that produces a fair amount of light.

Darren Hall posted this genius improvised bow made from a bike wheel and parts you can find in any hardware store, and shares his step-by-step instructions on Instructables.com.

Need to cross a river or lake without being devoured by alligators, frozen to death, or drowned by your gear? Simply lay out a tarp and pile small lightweight branches (the idea is to fill it with buoyant materials that will also create plenty of air pockets) in the center, then wrap the ends up and bind the entire raft with paracord or string. Be sure to test your raft thoroughly in shallow water to ensure it will carry your weight and not fall apart before venturing into deeper water.

If you have kids, you likely have far more crayons lying around the house and in the couch cushions than will ever be needed—these make great emergency candles.

Anytime you venture into the wilderness, you should carry a few pieces of chalk—ideally, those giant sticks of sidewalk chalk. If you happen to get lost, marking your path along the way (on trees and/or rocks) are useful both to ensure you don’t wander in circles and to help search and rescue crews track you down. The chalk is environmentally friendly and will eventually wash away. Hopefully, after you’ve found your way home or been rescued.

You can make a super simple, super effective improvised arrow or spear head from an old circuit board. Enough said.

Simply plug a wick into a can of Crisco to create a makeshift candle. This is about the same brightness as a typical candle, but it lasts much longer. I’m told it will burn continuously for 30 days, but I’m not sitting around long enough to verify that. Bottom line: it burns for a really long time.

This will make you think twice about the crap you’re putting into your body. Doritos and most other snack chips are highly flammable and make great tinder. You’ll just need to weigh your needs carefully—will the calories in your belly or a toasty fire be more valuable based on your current food supply, environment, and physical condition?

Improvised weapons come in handy, and we all know duct tape fixes everything. This takes it a step further using duct tape to create things; in this case, arrow fletching. Simple, cheap, and effective—what more could you ask for?

I want to emphasize that while you can use an egg to plug a hole in a leaking radiator, this is an absolute last resort. It may or may not work (it depends on heavily on luck because a bit of egg must lodge into the leak) and may cause permanent damage by plugging up your heater core—so only use this technique if it’s your only way out of a survival situation.

In the tropics, rain may just present an inconvenience; in the Marine Corps, we routinely patrolled in the rain, but in colder climates, getting wet can lead to hypothermia which can quickly lead to death. If you have a few garbage bags in your bug out bag (and you should), just cut a few holes and you have an instant rain jacket. You won’t win any fashion awards, but you will stay dryer and warmer.

Eyeglasses are essentially a pair of magnifying lenses. They can be used to collect and focus sunlight into a concentrated beam of light that can easily ignite tinder to start a fire. You can also use a camera lens or other curved clear glass.

A mousetrap and a cyalume glow stick is a simple, cheap way to set up a perimeter alarm system. This won’t make much noise so it requires someone constantly watching for a glowing light to appear. Ideally, keep your tripwires short and use more alarms so that you can more precisely identify the location of intruders.

A gorge hook is one of the simplest fishing tools known to man, and has been used since the beginning of recorded history. Simply whittle a short piece of wood to a point of each end and a groove in the center. Then tie string or fishing line tightly around the groove and embed the hook into your bait. When a fish swallows it and tension is applied, the hook will turn sideways, lodging in its gut, making it easy to pull your next meal in.

Most people don’t have an air compressor in their vehicle so how can they repair a flat tire? A short-term solution is to cut small holes into the sidewall and fill it with grass until the tire is relatively firm. When you get back to safety, you will have to replace your tire—there is no repairing this—but the key is that it will enable you to get home.

I have a particular fondness for re-purposed tools, and this mini-knife is a perfect example of that. Most of us have a few old hacksaw blades, and once they become dull, turning them into a new tool is a far better option than simply throwing them away. Here’s the beauty: all you need to create this is an old hacksaw blade and a metal file.

Headlamps are great until you try to talk to someone wearing one. Then you just feel like every redneck who claims they’ve been abducted by aliens. The solution is to turn your headlamp inward, facing a 5–gallon jug of water. Between the translucency of the plastic and refraction of the water, light gets bounced all over the place, creating an area light similar to a lantern, rather than a focused beam like a flashlight.

Improvising a bow is simple: bind several flexible reeds, like bamboo, tightly together tiered by length. You’re not going to get the same power as your $600 carbon fiber compound bow, but you can produce enough power to take down most two and four-legged predators.

A fist full of keys make a powerful, yet discreet weapon that you always have handy and can be carried anywhere without arousing any suspicion.

Corrugated cardboard doused in anything flammable (paraffin wax, oil, lard, etc.) and packed tightly into an Altoids tin can be used as a lantern that fits in your pocket. A side benefit is that when you close it (it will go out immediately) you can toss it into your pocket for added warmth, or even use it as a hand warmer.

The ingenuity of humans never ceases to amaze me. A boat can easily be made from trash, such as water or soda bottles, milk jugs, 5–gallon jugs, etc. Most Americans live the easy life, rarely stepping outside of relative safety, but think about the number of people who have fled Cuba on rickety boats just like this.

Keeping perishable foods cool without power is not a new technology—our ancestors have done it long before refrigeration existed. With two terracotta pots, sand, water, and basic physics, you’ll be in business. Place some sand in the bottom of the larger pot to raise the smaller pot the same level, then fill the space between the two with more sand. Place your fruits and vegetables in the center pot, and pour water in the sand between the pots. Evaporative cooling will draw heat away from the smaller pot, keep them nice and cool. A few important recommendations: your smaller pot should be glazed, neither pot should have a hole in the bottom, and you should cover the whole unit with a wet cloth.

Building a reed boat is time-consuming, but worthwhile because they tend to be far more durable and maneuverable than other improvised methods like the tarp raft I mentioned earlier. Build up a bundle of reeds thick enough that you can just fit your hands around it, and bind them with the inner strands of paracord or other string. Repeat this process until you have enough bundles to form a solid base and sides. The key is binding your reeds tightly—both when binding the individual bundles and when binding the bundles together.

A decent-sized empty can and a sturdy knife allow you to make a small stove that helps focus the heat of your burning fuel on your cooking device. (Pot, pan, skillet, etc.)

It can be a pain to place your seed holes at a consistent distance and depth when you need to cover a large area, but this tool stamps them all at once. If you need to cover a larger area, you can either build a larger version or simply stamp and move.

All you need is a hacksaw to turn an empty shell casing into a very loud signaling whistle.

A length of string can be used to twirl a cyalume glow stick as a signaling device, making it much more obvious and visible from a greater distance.

These simple no-frills fishhooks can be made by clipping away metal with your Leatherman a filing them to a point.

Achieving sufficient caloric intake can make a big difference in your chances of survival, and crappy food can make that tough. Some people are easier to please than others; give me a bottle of hot sauce and I’m happy to eat damn-near anything, but your neighbor may think he can’t eat a meal without a gourmet selection of herbs and spices. Regardless of which category you fall into, why eat crappy food when it’s as easy as filling a few Tic Tac containers with your favorite herbs and spices?

A tarp makes an improvised shelter that can be broken down in a hurry. Just be sure to add a drip line unless you’re a masochist who enjoys Chinese water torture.

During the Civil War, troops were told to keep their powder dry. Today, you have more important things to worry about, like keeping your TP dry. It’s easy to make a toilet paper dispenser from an empty coffee can, protecting it from the elements and ensuring a clean fresh bum as long as you have a supply of toilet paper.

Depending on your environment, good tinder can be hard to come by, but you can make your own by covering cotton (cotton balls, dryer lint, maxi pads, etc.) in paraffin wax or petroleum jelly. A Ziploc bag full holds plenty for even an extended outing and weighs next to nothing.