I'd be happy to! Tomatoes are super forgiving and are a great place to start.

The easiest thing is to pick up a seed packet at a garden supply store. I buy most of mine online or from Stokes. Drying out seeds is fairly easy, but seed packets are less work.

For starting seedlings you only need a few simple supplies. Ideally you have very light, "airy", soil. This usually sold as "seed starter" mix. You can make do with normal potting soil, or even whatever you can scrounge up from outside, but the seedling has to push its way up to the surface. So if your soil is chunky, or has stuff like woodchips in it, a seedling might struggle to breach the surface. A cheap way to make seed sprouting mix is to pass dry soil through a sifter. You can dry soil in the oven at a low temperature, but it's a bit stinky.

You should plant each seed around a 1/4 to a 1/2 inch deep in the soil. I usually lightly poke the soil with my pinky, drop one seed in the hole, and brush some surrounding soil over top. The important thing here is to leave the soil as loose as possible, so don't compact the soil at all if you can help it. Like I mentioned above, the sprout has to poke its way out all on its own, and it's not very strong. You can plant it deeper, but it'll take longer to reach the surface, or may not at all.

The ideal place to plant seedlings is in a covered seed tray, though any type of pot will do. If you have a bigger pot, you can plant a bunch of seeds in the same pot. You'd be surprised how big a plant can get in a tiny pot (maybe 2 cubic inches) before running out of space to spread its roots. If you have a good liquid fertilizer (I have a big jug from a hydroponic supply store that I've been going through for two years now) you can basically grow it anything. Some people use clay pellets or rockwool. A plant needs something to hold onto as it grows. Soil is convenient in that it provides both structure and nutrients, and it's what you already have outside.

Keep your seedlings in a warm place and never let them dry out. I like using a spray bottle to avoid disturbing the soil when things are just getting started. A covered seed tray keeps the moisture and heat in. Plastic wrap, or some other clear cover works fine in a pinch.

Once the plants start getting their "true leaves", i.e. the second set of leaves that look different from the initial seedling leaves, you can remove the cover to give it space to reach up.

Most tomatoes need staking (one wooden stake is ideal, bamboo is great, metal cages are common but I find them annoying) to keep them upright once they start getting flowers. Loosely tie the plant to the stake with yarn or twine.

If you intend on keep your tomatoes in a pot instead of the ground or some sort of raised bed, make sure the pot is fairly large and either has a drainage hole or some rocks at the bottom of it for water to pool. You never want the soil to be soupy.

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Edit: not super concise, sorry about that :) Feel free to ask any questions you might have. Also, don't be afraid to experiment. I was lucky enough to have a mother who grew up on a farm teach me most of what I know, but it really just boils down to:

light + nutrients + water + heat = food

The art is knowing how much of each.