Excellent question.
This is my first bucket plant (thanks to the #5gallonchallenge), so I had to figure it out as I went. No transplanting means starting in the largest possible container (bucket), especially doing it the way I do it (never adding anything except water) because the container has to begin with all the nutrients that will ultimately end up in the plant and flowers.
When it was just a little seed (and then a tiny sprout), I didn't want to water the entire bucket, so I just gave the seedling the amount I thought it needed. As the roots grew downward, I estimated how much water the plant needed each time, hoping to get the roots wet, but not drench the entire bucket. At this point, I assume the roots are pretty much all through the soil, so I'm giving it deeper waterings. Yes, generally I let the soil surface get almost totally dry before watering again. Because the plant is so lush now, it's shading the soil from most direct light, which means it isn't evaporating as quickly. That's good, but I'm watching for mold. So far so good. In two months it has had about 10 waterings. When it was smaller I misted it occasionally but I don't think it needs that now.
I don't know if I recommend growing in buckets, but it's definitely interesting, and providing me with learning experiences so that's great. And hey, sometimes all you've got is a bucket! Might as well know how to grow in one :)