These should give you a better picture of the process – although the collection is incomplete.
Oh, the marvellous tomato plant! This video shows an easy way to make clones of your tomato plants from otherwise discarded foliage. You’d prune off those extra shoots as a matter of course because they take energy away from the plant that you want it to spend on producing tomatoes.
This would be a good way to skip the seed starting process entirely — if a friend or community garden is willing to let you have a shoot.