Germination is easy. Sow on the surface and keep at around 50F. Don't allow the surface of the soil to dry out until after the seeds have germinated. Either spray regularly or keep covered with glass or plastic.

200 seeds would be more than enough for a large seedtray, just 5 or 10 in a pot. You could even just sow three and kill any more than one that come up, if you only want a single plant.

Good light is important, full sun is good if you keep the plants cool.

Hmmm .... I just see that you are in the desert, not a good place for this plant. It will probably need to grow indoors in an air-conditioned room and even then might not be too happy. Maybe an east window so it is protected from sun in the afternoon but still has bright light. Maybe you will just grow it as a winter annual?