Some canning basics, in case you think only other people can perform this magic.

There are two kinds of canning, water bath canning and pressure canning. Some things can only be pressure canned because of their ph levels or density. I’m going to leave pressure canning to someone more knowledgeable and talk about water bath canning, which is safe for high-acid foods. If a recipe calls for pressure canning you absolutely cannot substitute with water bath canning.
There are three important things to remember while canning. The first is, “hot food, hot jars.” Your jars should be sanitized and hot, and they will be filled with hot food. The second is, ‘be clean to be safe.’ Clean hands, clean jars, clean pots, clean utensils (metal’s best), clean towels. The third is, ‘trust your source.’ You don’t want to wing it when canning. Make sure the source of your recipe is someone who understands the canning process. Your great grandparent, while undoubtedly the source of some stellar life advise, may or may not be the best source for canning recipes, as understanding of food safety has developed quite a bit in the past fifty years. The best way to decide who is trustworthy is to understand the process yourself, so do some reading. You’re off to a good start with this post. Ball (maker of jars) has a website full of great information. You can feel confident using any recipe on their site.
At some point you’ll likely see lemon or lime juice used in a recipe. They are used to increase the acid level when the food itself does not have enough to can safely. It is important to use the amount specified, and to use bottled juice, not fresh. Bottled juice is required to meet certain acidity levels, whereas levels vary in fresh fruit. Vinegar is also used to increase the acidity of foods. Do not improvise on quantities – prepare the recipe as written.
There are some supplies you’ll need:
1) A large pot with a rack of some sort on the bottom to boil the jars in. This is your water bath canner. The rack keeps the jars off the bottom of the pot. Full disclosure, I canned for years without a rack and had no problems, but a rack is proper procedure. You can rig one with rings from old jars if necessary. There are canning-specific pots sold, but any pot big enough to hold your jars and allow them to be covered by at least an inch of water will do. These days I can in a beautiful two-burner Amish canning pot, but for a long time I used a cheapo stainless pot.
2) A large pot to cook your food in. Many times the food you’re canning will expand as it boils, so you want something that gives you a lot of space on top of the food. Because you’re cooking high-acid foods, you do not want to use aluminum or cast iron, which are reactive. If you’re buying a pot and not just using one you have, I’d go for stainless steel, get the biggest you can, and make sure it has a nice thick bottom. That will prevent any sticking or burning.
3) Tongs and/or a jar lifter. Jar lifters are very handy, making it about a million times safer to move your very hot, full jars from counter to canner and back again. It is possible to use a long set of metal tongs, though, if you move very carefully, and I prefer to use tongs when moving empty jars.
4) A wide funnel. This will cut down on the amount of food that ends up on the outside or on the rim of the jar, helping keep things clean.
5) Towels. I like to have a stack of very clean dishtowels and also some larger towels to line the counter so my hot jars don’t experience a sudden temperature change when they’re placed on it. The dishtowels should be a flat weave, with no fuzzies that might make their way into your food. I use flour sack towels.
6) Canning jars. These comes in various sizes, so choose the one that’s right for your product and make sure that you follow the proper processing time for that size jar. Jars can be reused. Just make sure they are clean and without cracks or dings.
7) Two piece canning lids. These will consist of a flat lid which can only be used once and a ring which can be reused as long as it is not rusty or damaged. Flat lids can be purchased separately from jars, so you can reuse last year’s jars and rings and just replace the lid. It used to be recommended to simmer your lids, but Ball has reversed that recommendation and it is no longer necessary.
Ok, so what do you do with all this stuff?
Take the lids and rings off your jars.
Set the jars in the water bath pot and cover them with water.
Put that pot on the stove, cover it, and heat it to boiling, then turn down the heat and let it simmer.
Prepare your trustworthy recipe in your cooking pot.
Remove your jars from the hot water and fill with your completed food, leaving the amount of headspace (empty room on top) noted in the recipe.
If any food splatters on the rim or outside of your jars, wipe with a very clean dishtowel.
Cover the jars with clean, never been used lids, and secure with rings twisted finger tight.
Place your full jars back in the water bath, cover it, and turn up the heat to bring it back to a boil.
Once it’s boiling, set a timer for the amount of processing time noted in the recipe.
When time’s up, shut off the heat and let the jars sit for a minute in the water, then remove them and set them on a towel on the counter.
Don’t move them for the rest of the day, so as not to disturb their sealing. You will hear popping as they seal. You will develop a Pavlovian response to this noise.
The next day, check the seal by removing the ring and holding the jar by its lid. (Keep a hand underneath just in case!) The lid should be on very firmly. If your jar didn’t seal, your food is still just fine. It is not shelf-stable, however, and should be kept in the fridge. Failed seals happen to everyone, so take the time to check them.
Make sure the jars are clean, double checking under the ring, so that no mold will grow on the outsides. Wipe with a damp towel if necessary.
Label your jars with contents and date made.
Store your jars in a cool, dark spot. Best practice is to remove the rings so that if for some reason your jars should unseal it will be obvious. I will admit to not always following best practice in this area, but feel free to be more responsible than I am.
High-acid canned food is generally considered safe for one year, but that’s conservative. We’ve eaten lots that’s two years old. If it goes bad, you will know it – the seal will break, mold will develop, or the color or texture will be unappealing. When in doubt, throw it out, but if a high-acid food looks fine, it is. This does not apply to low acid foods, which you of course will not be water bath canning in any case, and which are the foods where botulism is a concern. You can’t see or taste botulism, which is why it’s important to pressure can when required.
A word on mishaps: Sometimes a jar will break in the water bath canner. It’s depressing, but don’t despair. Take out your other jars and clean them up, dispose of the broken jar, and move on. Very rarely, due to user error, a lid might come off during processing, leaving you with an empty jar and canning water filled with floating food. Again, not the end of the world, just follow the same cleanup process.
Whew, that’s a lot of information. Any questions, feel free to ask in the comments.