Jam making is both easy and difficult. Grandmothers have been jamming and canning for generations and passing their bounty (for ill or for good) onto their progeny. But for as straightforward as it can seem, there are many paths that lead to the same goal - spreadable, sweet fruit spread. All jams contain berries (duh), but the rest depends on how much work you want to do. If you want a firmer jam, you need pectin since strawberries have little natural pectin. You also need inhibit the growth of bacteria somehow. There are two main methods used - cold or heat. With cold, you have freezer jam where your end product sits in the freezer. The bitter cold prevents bacteria from growing. With heat, you have to immerse the jars of jam in boiling water for 10ish minutes in order to kill the bacteria either on the jar or in the jam. This method also seals the jar so it is stable at room temperature since it is (nearly) sterile.
I perused the internet to find my path and found it at Pick Your Own. These are step-by-step directions for strawberry jam using the heat method featuring many pictures and charts to help you on your way. I won't detail every step since the author(s) of that website have done a far better job than I (it is very difficult to remember to take pictures when your stirring molten berries or burning yourself with boiling water). I just want to point out some crucial details during the whole process.
First of all, make sure you have all of the ingredients before you start. In most cases this is a no-brainer since you know you need strawberries and most people have sugar on hand. I did not read the directions all the way through and did not see that you need 1-2 boxes of pectin (available in grocery stores by jamming and canning supplies). I would also HIGHLY recommend buying a ladle, a jar grabber and possibly a canner pot. Careful ladling makes the jar funnel unnecessary. The jar grabber is a pair of tongs modified for picking up jars by their necks while they're boiling. Don't assume you can do without because I definitely had to MacGyver a method mid-boil. I also have a very tall soup pot that I used, but a canner might work better if you don't mind another pot hanging around.
I used about 4-5 lbs of berries for 4 large Ball jars of jam. Without additional boxes of pectin, I was not able to get the berries as set as I would have liked, but they still set up pretty well. Plus, skimming excess foam from the berries is a delicious preview of your final product. Feel free to eat as much as you can stomach.
If you're starting from freshly picked berries, it will take a couple hours to clean, cut, cook, and can the jam, but it is so worth it. Think about it this way: I picked my berries at 8:00am and by the afternoon (I took time to see a movie) I had jam. From the vine to the jar to my toast in the same day. You can't get any fresher than that.