This is how I easily dehydrate tomatoes. If you grow tomatoes for the same reason I do, because there is nothing like a vine ripened tomato. The ones from the store taste like cardboard in comparison. There are so many varieties to chose from, so I grow more than one and they often come in 6 packs, I plant them all. What happens is a glut of fresh tomatoes. Here is one way I preserve tomatoes.
By dehydrating tomatoes, the flavors are concentrated. They taste great crumbled into salads, over pasta and added to spaghetti sauce The room needed to store them is just a fraction of the original volume.
I do use a dehydrator. A simple one I have had for 20 years. I imagine you could dry them in the sun if the humidity is not too high. If you can’t dry them fast enough, mold will grow.
To prepare, just wash and slice the tomatoes into 1/4″ thick slices, put in a single layer on the dehydrator trays, stack in the machine and dry until they snap when twisted. I suggest you do this in the garage- it does smell as the moisture is driven off. Store in freezer bags or airtight containers. If you store in the freezer they will last for years. You can also “can” and freeze tomatoes.