Please describe why it looks horrible. Also, presuming it's a result of your using annatto seed powder, how did you add the powder?
Before offering my suggestion, let me warn you that I'm a beginner, so don't put much faith in what I say until an expert has looked it over... But...
Did you remove some of the soap batter, mix the annatto in that, and then use that to swirl your batch? Or add the powder directly?
I think you should split your batch and thoroughly mix your colorant with one part, pour the uncolored batch into your mold, then mix in the colored part right in the mold. Anyway that's how I would try it the first time.
Again, I'm just a beginner. I haven't colored anything yet. No experience, just book and Internet knowledge. But learning.
BTW that annatto looks like it might make a pretty good colorant, particularly for those who want to stick to natural ingredients. I've got some annatto in my spice cabinet that I'm intending to try soon. Annatto has very little taste so presumably it shouldn't affect skin, eyes, etc. much. I'm also interested in trying tumeric and maybe paprika for the same reasons (worried that paprika might be too strong though). All the other spice colorants look a little too active to make me feel comfortable about using them in soap. You know, like cayenne? Very hot spicy. I'm not so sure about using cayenne in soap although I've read that others are using cayenne.
My first attempt will use annatto.