I strongly suggest you have a clean kitchen, counters decluttered and clean and an empty sink. This is a process that will take over your kitchen and you will need room and the sink. You will want a clean stove too. When you are well prepped, this always goes better. You need your jars and rings sterilized either in the dishwasher or by hand. They cannot be dirty.
With your strainer, you want to wash your tomatoes in the sink. I saturate them in some vinegar and let it soak for a bit and then start washing. Throw away any bad tomatoes. You do not want to process these ones.
With your stockpot or large saucepan begin to boil water. Once it's boiling use your metal chef basket to gently place the tomatoes into the pot. You will need a large bowl with ice and water on hand. You're waiting until the tomatoes begin to split, once that happens they're ready to come out and be placed in the ice to cool down. We are promptly cooling them because they will otherwise continue to cook from the heat and be impossible to handle.
We boil the tomatoes because it causes the skin to separate from the rest of the tomato without making a huge mess. Then typically only the top needs to be cut off. If I have someone helping me I have one person dealing with the tomatoes in and out of the boiling water and one peeling the tomatoes. If I'm by myself I gather all the boiled tomatoes and then start peeling. The skin and stem and any bad or buggy parts will be thrown away.
This is when I place the jars in the large pyrex glass dish. I use the mouth funnel to help keep the lip of the jar from getting too dirty as I add tomatoes. You want to pack the jar with the tomatoes so that their isn't too much air space.
Once you have all the jars filled add a 1/2 inch of salt if you desire. You will want to add 2 tablespoons of lemon juice to each jar. This helps make sure the tomatoes are acidic enough so that they cannot grow botulism. Tomatoes are right on the border so it's best to add an acid to guarantee you won't have an issue.
Boil water in another saucepan, as this water will be added to the quarts. As you carefully add the boiling water you need to leave 1 inch of headspace at the top of the jar. The Canning Essential Box comes with a device to help measure the headspace. That same device helps you get the water bubbles out of the jars as you push and stir everything around. You may need to add or take out water at this point. You can use any plastic spatula to help remove water bubbles for this (don't use metal though).
In a small saucepan add the lids and rings to the water, you want the water to boil and then move to simmer.
Use damp handtowels or wet paper towels and wipe off the rim of the jar to make sure no food is stuck to it. Once it is clean, I dip a paper towel in a bit of vinegar and wipe around the top to help make sure I will have a good seal.
The Magnetic lid lifter is wonderful in getting individual lids out of the water OR use your tongs (or try the fancy ones I use) to grab each lid. A fork can be helpful as well. I put the lid on, and then grab a ring. You can use the tool in the jar wrench to help screw on the lid (sometimes everything is super hot), but you must be careful that you only tighten it just until it closes. What causes the jars to seal is not how tight the rings are, but the seal on the lid. Tightening too hard can cause the jar to explode while processing.
At this point we have gotten to where I need to give instructions for each canner, so choose the canner you are going to use for the rest of the recipe.