Hunting and fishing

Most rifles should be good for hunting, as well as most shotguns, although sawn off shotguns would be ineffective due to shorter barrel and wider spread, as well as a higher danger risk. Some pistols might work, higher calibers prefered, like the .45. If firearms are unavailable or you just prefer not to, you can always use bows, crossbows and spears for a more silent approach. One advantage is that you can recycle your spent ammo. If civilization falls and we go back to hunting and gathering, then those might end up being our only weapons. What, on the other hand, should NOT be used as weapons are:
Automatic fire - Using automatic fire is not only a waste of ammo when one bullet should be enogh, it also makes it harder to clean the meat before cooking and destroys the skin that can be used as warm clothing or armour.

Incendiary - If using flamethrowers to hunt for food and animal pelts is not a good enough reason for you, then you should also know that most incendiarys use chemicals wich are poisonus and you would not want in your food. The Flammenwerfer 35 is a German flamethrower that uses mainly petrol, tar, and hydrogen. Things that you don't want in your food. When using a flamethrower to foolishly hunt prey, you are basically burning the animal to death. That includes burning the meat and fur to a useless crisp.

Hunting rare animals - you don't want your food source to become extinct. Even if you don't hunt that creature much you should not forget what importance it may have in the food chain.

Meat bait - Not only will this attract zombies, but they will put your safety at risk, and animals at risk of the although unlikely event of getting eaten by a zombie.

When hunting in a zombie outbreak, you must be quick and quiet when you go out for food. It is good if part of the group go out and hunt while others stay behind.

Ambush
An old, simple, but effective tactic. An animal, or a herd of animals is lured or scared into a closed place where hunters kill them.

Traps
Traps have also been used for hunting, though they have been banned in most countries now. Simple trap like falling pits or snares can be very effective.

What you will hunt and how you will hunt will always depend upon the terrain. In some terrains there will be plenty of easily found animal life, in others they will be hiding easily and is some prey will be just plain hard to find.

Plains
Be it the African savannah, American or Middle-Asian steppes or something else, two things would mostly affect your hunt there. The vast area without hideouts, and often herds of large mammals can make your hunt pretty easy. This also represents a problem due to how easy it is, humans have often hunted many of those large animals to near extincion. If the plains you are hunting in is like Saskatchewan, you might be better off somewhere else because a zombie could see you a kilometer away or the gun you just shot echoed far enough for one to hear, and then follow. Plus there is not many animals (in clear view) are in Saskatchewan unless you count on raiding the local grain and canola farms.

Deserts
Deserts are one of the most dangerous enviroments on Earth. They are different as they are found on many places on the planet but have two things in common. Extremes in tempature, being either extremely hot or extremely cold, and being dry. Relying on hunting as a main foodsource is not advised. There are rarely large prey in deserts but if they are, they are scarce. It would be best for you to not be too dainty as you will likely have to add insects on the menu.
List of (possible) prey:

Camels: Large amount of meat (but likely very scarce).
Scorpions: Very little amount of meat, it's risky to kill them and you can only eat them only cooked in oil. One should not rely on hunting them.
Snakes: Even if it's risky, the amount of meat you can get from them is actually quite a lot.

Jungle
Rainforests and other tropical forests, although haveing been rapidly decreased in size by humans, still habit some large areas on the planet and house the most variety of animal-and plantlife. Therefor may there be found large varietys of prey, both large and small. Still, many of the larger ones may already have been hunted in large quantities and therefor be hard to find, so you should be prepared to add insects on the menu. A good tip would be to look up as many animals (monkeys, birds, etc) often spend their whole life up in the trees. Tree-climbing skills could be helpful there. At last you should be careful not ending up as prey yourself, as large predators wich are experts in sneaking up on their prey are found there, and large numbers of venomous insects and snakes.

Tundra
Tundras are, most of the time, grown with pine or sesonal forests, wich can hide your prey, but also provide hideouts for you while sneaking up to it or ambushing it. During summers, a plenty of migratory birds will come to raise their young, especialy near the sea. Still beware that some of them, like the arctic tern, gather in very large groups and attack anything that might threaten their young. All year round there are some large game, like reindeer (caribou), elk, moose, deer or bear.

Arctic
Hunting on the polar region is hard business. Animal life is scarce and fish will proabably be the most important food source. To hunt, it would be best to copy the ways of the master arctic hunter, the polar bear. It mostly hunts seals and was it's tactic used for ages by the Inuits. They ambush seals by holes in the ice, which the seal uses to breath. This tactic is also harder now due to melting icecaps. In the Antarctic you can also add penguins on the menu. They often lay eggs in extremly large groups. You should still never kill to large portion of them as the stock may never recover, leaving you without good source of meat on a place where you can't afford that.

Urban
When the humans, or at least large portions of humanity, will disappear, nature will quickly start claiming land back. Of course hordes of hungry zombies dwelling in urban areas will proabably hinder that in many ways. Still wild animals would many seek shelter in abandomed suburbs, towns, and even cities where the number of zombies is not overwhelming. The predadors would then follow. Many animals would proabably by able to defend them self with horns, claws, teeths, reflexes and strength superior to humans (and zombies). Hunting in abandoned urbans would be easy to do providing you have large numbers of hideouts were you can sneak up or ambush your prey, and dead ends were it can be cornered and killed easily, just don't forget who the possible prey could be. Also, traps can easily be set, like in narrow entries like doors, deadfalls, pitfalls, or net traps

More inexperienced hunters can, during the first months, hunt the animals that local farmers had, if they have survived. As domesticated animals are normally more used to humans, sneaking up and hunting them would not be as hard as with wild animals. Just be sure that the owner has fled or died because you don't want an angry, armed farmer added on the list of things trying to get you because he/she may have needed them for their own food sources. If the prey is a cow or a chicken, then killing it isn't always your best bet per sey. Cows can be kept for milk and chickens can be kept for eggs for your breakfast omelette.

Effective ways to get fish include...

Using a fishing rod with bait

Using a net

Explosives can be used to briefly stun fish. (this is one of the more effective ways, but carries a great deal of hazard)

Using electricity is also very effective, however risks still exist. An electric fence unit is a good, low current way to provide the volts required to temporarily stun the fish.

Varius poisons can be used to stun fish, however availabilty and safe use depends on location and prior knowledge.

A spear can be used to secure fish, but it requires a great deal of skill.

Fishing at a fish farm if theres any near.

If your location is near a sport fishing lake, then you should make this your first priority in fishing.

Bait can be found by digging in dirt until finding worms, or breaking apart rotting trees(or under moist rocks) for grubs or bugs that local fish enjoy eating. If no bait is acquired, then using the average fishing lures can work just as well.

Fish hooks are frequently lost, however, a gorge hook is easily made from nearly anything and is every bit as effective. Fish can not be, however, released when caught with such a device.

Keep in mind what kind of fish you are fishing for. If its big enough, is there enough, is it poisonous (blowfish, etc.) do you know how to cook it? And what bait/lure to use to the respective fish.
Fishing in cold waters would mean you should use cold colours, such as white, grey, silver, blue, black, and purple. Fishing in warm waters would mean you should use warm colours such as red, orange, yellow, pink, gold, etc.

Pickeral
Walleye like many colours ranging from gold, yellow, red and orange, to green, silver and blue, but try sticking to warmer colours.

Bass
Bass tend to like greens.

Pike
Jack tend to like mostly any colour. Green, red and black, and dark blue are good.

Rainbow Trout
Found in shallow rivers prefer a red and white daredevil no longer than 2 inches in length including the hook. No bait is necessary but its helpful.

Speckled Trout
Can be fly fished in fast flowing rivers and streams but in lakes, use gold and silver with a size 1 hook and a worm.

Perch
On a good day with 2 other people, 100 perch can be caught in 6 hours but they are small. Use a size 16 hook with a cold, cut, cooked piece of shrimp no bigger than your pinky finger nail. Use a 3-4 inch slip bobber and 4 pound test like in case you catch a small pickeral or bass.

Goldfish
Can be found in ponds. Those in fish stores and homes will probably be dead several days after their owners abandon them. They can be found in their natural environment in ponds in China, but are also commonly found in ponds.

Just like everything else, fishing is not without dangers. The most obvious one in zombie infested world is of course a zombie horde attacking but there are also many dangers not related to them. When fishing in rivers with strong current you need to be careful to not fall in the river or let it grab you. Similar when you are fishing on lake from a boat or pier. Even though you can swim, there is always possibilty of a roaming zombies or local animals (crocodiles, pirhanas, stingrays and more). Also are many dangers simply in the water and fish. Humans have dumped all kinds of waste to rivers and lakes, and even if it has decreased, the danger of polluted fish and water still exists. Also when humans are running for their lives from zombies, things like checking if tanks full with toxins are secure. So when picking a lake/river/or just whatever body of water that houses life,be sure to check for possibles of toxic spills. Also having local fishing experience and/or chemist can be very helpful to deem if fishing is safe.