Yet another star and some design sighs

Lots of things has happened lately, so I haven't found the time to scan this star I made a while ago, when I was staying a couple of days at my parents place.
I still haven't found out whether I dare iron this metallic yarn or not, so if it looks sloppy I hope that's the reason. :P
I need to make many more, if I want to keep the promise I made to myself.
How ever it's a lot more fun to work on a new pattern for the design class. I'm very proud of the looks of it *beaming with pride*, there is just one "slight" detail that is troubling me at the moment. How on earth am I supposed to find the right number of stitches for the design? It looks so nice on paper, but I'm quite sure it won't look anything like it at all, if I try tatting it with the numbers I've tried so far. Making your own patterns is indeed a lot harder than one should think, and I didn't expect it to be easy.