I have been saving seeds of all kinds. These Sunflowers are grown from seeds saved during previous seasons. This is the dwarf variety; tiny seeds, and lot of flowers. It's a delight to see them.
In 8" pots, we have two dwarf plants each. May seem crowded but no; their stems are thin and tall, and leaves are small, and therefore, two plants grow well. We ensure that one plant is manure, the other one is seedling. This way, when the manure plant stops flowering, the seedling would have grown manure enough to flower.
The potting mix is red mud, cocopeat, and manure; well-drain soil. During flowering season, I add a handful of manure/vermi-compost to the top soil, and mix well. Yes, these plants love direct sunlight. Needs water almost everyday, depending on the temperature. Search the plants for caterpillars, and if found, remove them.
After the flower dries, cut them, and save them for the next season. Here sunflowers grow throughout the year, and that's a beautiful gift. :-)