http://www.youtube.com/watch?v=BO3uAibfF8U&feature=related

If you make this buttercream carnation, would you make it directly onto the cake or on a nail and then transfer it directly to the cake?

On a nail for a full carnation:
http://www.wilton.com/technique/Carnation

Directly on the cake for a half carnation:
http://www.wilton.com/technique/Half-Carnation

I have to say that not one of the sites I've visited does a carnation like I think a carnation should look. But in my trial and error for making buttercream roses I think I may have a solution for me.

One of the problems I'm having with my roses (why this time and never before- I do not know) is that the edges are fraying as I make the petals. They split and tear and I can't get them smooth. I'm almost done so I'm not going to bother to fix it so instead I've found that if I just change the center of the "rose" - as in, don't even bother to make that ribbon that becomes the center of the rose. Make it like you would a rose just skipping the center ribbon and bringing the 1st 3 petals as close as you can. Let them fray and tear.. it's a better carnation that way. I think, anyway.