A girl who's graduating just got a pot with a pretty little flower in it from her a capella group as a parting gift. She's about to fly away across the world, so she can't take it with her, so she gave it to me to tend to.
Now that we some background, just for interest: First I try to ID the flower. I'm 90% sure it's a French marigold. Looks almost exactly the same, but can't be sure and I don't have a camera to show you at the moment.
But assuming it is, I see that this is an annual, and can be expected to die. But I also see that it's possible to resurrect the plant through its petals, which apparently function as seeds.
Can anyone explain to me (quite thoroughly, as though to an idiot) how and when to do exactly what in order to keep this plant alive for the whole season, and to bring it back in future seasons?