Step 9: Harvest
You can cut or twist the fruit off when it is fully colored. Some heirloom varieties ripen green or have green shoulders when ripe; Google the varieties you are growing to see what they look like when ripe.
From this point forward, it's mostly watering and picking fruit till the season ends.
Here are a couple useful links to help with any problems the tomatoes may have:
Diagnose tomato disorders/diseases