"Squish them out into a jar," Chetelat said. "Let them ferment on counter. The fungi will work on fruit pulp. Rinse in a strainer and pop the seeds onto paper to dry them." (UC Cooperative Extension offers more detailed instructions on how to save tomato seeds.) Store seeds in a cool dry place, then start them inside next April. Ninety days later, you should have fruit, probably closer to the Fourth of July than Memorial Day, unless something wonderful happens.
Be sure to check out that excellent link she recommends for more detailed info. I do the same as above but with one change: I dry my seeds on coated paper plates. If using paper, I found the seeds tend to stick while drying, becoming one with the paper. Not a good thing.
I have a different take on starting seeds, perhaps my adjustment to being close to the beach. I find April on the late end to begin. Though not as warm as inland, our weather is actually milder and less extreme in terms of the night time low temps in the winter. I actually start my seeds as early as December, indoors, though I may have to change this since our new place doesn't seem to get as much windowsill sun. I can get the earliest plants into the ground by February. I keep planting, however, to May at the latest. I only plant cool climate tolerant tomatoes because they have fewer issues with our cloudy and foggy summers.